“ Green” Transportation Taxes and
Fees: A Survey Of Californians
MTI Report 08- 05
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MTI REPORT 08- 05
" GREEN" TRANSPORTATION TAXES AND FEES:
A SURVEY OF CALIFORNIANS
June 2009
Asha Weinstein Agrawal, Ph. D., Jennifer Dill, Ph. D.,
and Hilary Nixon, Ph. D.
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MTI 08- 05
Asha Weinstein Agrawal, Ph. D., Jennifer Dill, Ph. D., and Hilary
Nixon, Ph. D.
This report explores public opinion on a new and promising concept― green transportation taxes and fees. These
are taxes and fees set at variable rates, with higher rates for more polluting vehicles and lower rates for those that
pollute less. This approach to transportation taxes and fees adapts the traditional transportation finance system to
achieve two critical public benefits at once: encouraging drivers to choose more environmentally- friendly
transportation options and raising revenue for needed transportation programs.
To test public support for green transportation taxes and fees, the authors conducted a random telephone survey of
1,500 Californians that asked respondents their views on five hypothetical tax and fee options: a flat- rate and a
green vehicle registration fee, a flat- rate and a green mileage fee, and a “ feebate” program for new vehicle purchases
under which more- polluting vehicles would be charged a tax and less- polluting vehicles would receive a rebate.
The survey results show that the concept of green transportation taxes and fees strongly appeals to Californians.
The survey tested this in two ways: by testing support for the three hypothetical green transportation tax and fee
policies, and also by comparing support levels for flat- rate versus green versions of two taxes. Majorities of the
respondents supported all three green taxes and fees tested.
Another striking finding from the survey is that support for the green taxes and fees did not vary greatly by
population subgroups; a diverse range of Californians supported the green taxes and fees. An analysis comparing
support for the green and flat- rate vehicle registration fee and feebate proposals confirmed that in every subgroup,
more people within that subgroup supported the green than the flat version of the two taxes tested.
Environmental protection;
Finance; State taxation;
Registration fees; Revenues;
Taxation; Taxes
128
CA- MTI- 09- 2701
" Green" Transportation Taxes and Fees: A Survey of Californians
by Mineta Transportation Institute
All rights reserved
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Mineta Transportation Institute
College of Business
San José State University
San José, CA 95192- 0219
Tel ( 408) 924- 7560
Fax ( 408) 924- 7565
E- mail: mti@ mti. sjsu. edu
http:// transweb. sjsu. edu
Copyright © 2009
Library of Congress Catalog Card Number: 2009931100
ACKNOWLEDGMENTS
The authors would like to acknowledge and thank the following people for their important
contributions to this project.
Thank you to research assistants Vicki Sherman and Dennis Freeman, and well as to Phil
Trounstine, director of the Survey Policy and Research Institute at San José State University,
who managed the survey implementation and provided advice on the questionnaire design.
EMH Opinion Sampling, Inc. conducted the telephone interviewing.
Finally, thanks are offered to Mineta Transportation Institute staff, including Research
Director Trixie Johnson, Communications Director Donna Maurillo, Research Support
Manager Meg Fitts and Publications Assistant Sahil Rahimi. Publishing and editing services
were provided by Catherine Frazier.
Mineta Transportation Institute
i
TABLE OF CONTENTS
EXECUTIVE SUMMARY 1
INTRODUCTION 7
FINDINGS FROM THE LITERATURE 15
Transportation Finance Measures Linked to Environmental Outcomes: A Review of
Public Opinion 15
Factors Correlated with Pro- Environment Behavior 19
SURVEY DESIGN AND ADMINISTRATION 23
SURVEY RESULTS 27
Survey Respondents 27
Support for the Green Transportation Taxes and Fees 30
Support for Green ( Variable Rate) Versus Flat- Rate Transportation Taxes and Fees 46
CONCLUSIONS AND RECOMMENDATIONS 55
Summary of Key Findings 55
Policy Implications for Transportation Professionals and Policymakers 58
Recommendations for Future Research 59
APPENDIX A: SURVEY QUESTIONNAIRE AND TOP- LINE RESULTS 61
APPENDIX B: POLICY SUPPORT BY SOCIO- DEMOGRAPHIC CATEGORY 73
APPENDIX C: POLICY SUPPORT BY TRAVEL BEHAVIOR 79
APPENDIX D: POLICY SUPPORT BY TYPE OF VEHICLE RESPONDENT
DRIVES MOST 85
APPENDIX E: POLICY SUPPORT BY OPINIONS ON AIR POLLUTION,
TRAFFIC CONGESTION, AND TRANSPORTATION SYSTEM QUALITY 91
APPENDIX F: POLICY SUPPORT BY OPINIONS ON TRANSPORTATION
REVENUES PRINCIPLES OF STRUCTURING VEHICLE
REGISTRATION FEES 95
ii Table of Contents
Mineta Transportation Institute
APPENDIX G: POLICY SUPPORT BY KNOWLEDGE OF TRANSPORTATION
ISSUES 99
APPENDIX H: POLICY SUPPORT BY OPINIONS ON ENVIRONMENTAL
POLICY ISSUES 107
ENDNOTES 111
ABBREVIATIONS AND ACRONYMS 117
BIBLIOGRAPHY 119
ABOUT THE AUTHORS 125
PEER REVIEW 127
Mineta Transportation Institute
List of Tables iii
LIST OF TABLES
1. Findings from a sample on flat transportation taxes to improve the environment 17
2. Findings from surveys on variable environmental taxes or fees for transportation 18
3. Socio- demographic characteristics of survey respondents and of all Californians 28
4. Travel behavior information and data about the vehicle respondents drive most often 29
5. Statewide support levels for the five transportation tax and fee options 31
6. Support for the green fee policies, by socio- demographic categories and region 33
7. Support for the green fee policies, by travel behavior 35
8. Support for green fee policies, by type of vehicle respondent drives the most 37
9. Respondents’ opinion on air pollution, traffic congestion, and transportation system
quality 38
10. Support for the green fee policies, by opinions on air pollution, traffic congestion, and
transportation system quality 39
11. Respondents’ opinions on transportation revenues and principles of structuring
vehicle registration fees 40
12. Support for the green fee policies, by opinions on transportation revenues and
principles of structuring vehicle registration fees 41
13. Respondents’ knowledge about transportation finance and about the link
between motor vehicle use and the environment 42
14. Support for the green fee policies, by knowledge of transportatoin and environmental
issues 43
15. Respondents’ opinions on policy topics 44
16. Support for the green fee policies, by policy preference 46
17. Difference in support for the green vs. flat- rate registration and mileage fees by
socio- demographic categories 48
18. Difference in support for the green vs. flat- rate registration and mileage fees,
by travel behavior 49
19. Difference in support for the greeen vs. flat- rate registration and mileage fees,
by type of vehicle respondent drives most 50
20. Difference in support for the green vs. flat- rate registration and mileage fees,
by opinions on air pollution, traffic congestion, and transportation system quality 51
21. Difference in support for the green vs. flat- rate registration and mileage fees,
by opinions on transportation revenues and principles of structuring
vehicle registration fees 52
22. Difference in support for the green vs. flat- rate registration and mileage fees, by
knowledge of transportation issues 53
iv List of Tables
Mineta Transportation Institute
23. Difference in support for the green vs. flat- rate registration and mileage fees,
by opinion on environmental policy topics 54
24. Support for the flat- rate vehicle registration fee, by socio- demographic categories
( detailed breakdown) 71
25. Support for the green vehicle registration fee, by socio- demographic categories
( detailed breakdown) 72
26. Support for basic mileage fee, by socio- demographic categories ( detailed breakdown) 73
27. Support for the green mileage fee, by socio- demographic categories
( detailed breakdown) 74
28. Support for the feebate, by socio- demographic categories ( detailed breakdown) 75
29. Support for the flat- rate vehicle registration fee, by travel behavior
( detailed breakdown) 77
30. Support for the green vehicle registration fee, by travel behavior ( detailed breakdown) 78
31. Support for the flat- rate mileage fee, by travel behavior ( detailed breakdown) 79
32. Support for the green mileage fee, by travel behavior ( detailed breakdown) 80
33. Support for the feebate, by travel behavior ( detailed breakdown) 81
34. Support for the flat- rate vehicle registration fee, by type of vehicle respondent drives
most ( detailed breakdown) 83
35. Support for the green vehicle registration fee, by type of vehicle respondent
drives most ( detailed breakdown) 84
36. Support for the flat- rate mileage fee, by type of vehicle respondent drives most
( detailed breakdown) 85
37. Support for the green mileage fee, by type of vehicle respondent drives most ( detailed
breakdown) 86
38. Support for the feebate, by type of vehicle respondent drives most ( detailed breakdown) 87
39. Support for the flat- rate vehicle registration fee, by opinions on air pollution, traffic
congestion, and transportation system quality ( detailed breakdown) 89
40. Support for the green registration fee, by opinions on air pollution, traffic congestion
and transportation system quality ( detailed breakdown) 90
41. Support for the flat- mileage fee, by opinions on air pollution, traffic congestion, and
transportation system quality ( detailed breakdown) 91
42. Support for the green mileage fee, by opinions on air pollution, traffic congestion and
transportation system quality ( detailed breakdown) 92
43. Support for the feebate, by opinions on air pollution, traffic congestion, and
transportation system quality ( detailed breakdown) 93
44. Support for the flat- rate vehicle registration fee, by opinions on transportation
revenues and principles of structuring vehicle registration fees ( detailed breakdown) 95
Mineta Transportation Institute
List of Tables v
45. Support for the green vehicle registration fee, by opinions on transportation revenues
and principles of structuring vehicle registration fees ( detailed breakdown) 95
46. Support for flat- rate mileage fee, by opinions on transportation revenues and
principles of structuring vehicle registration fees ( detailed breakdown) 96
47. Support for the green mileage fee, by opinions on transportation revenues and
principles of structuring vehicle registration fees ( detailed breakdown) 96
48. Support for the feebate, by opinions on transportation revenues and principles of
structuring vehicle registration fees ( detailed breakdown) 97
49. Support for the flat- rate vehicle registration fee by knowledge of transportation issues
( detailed breakdown) 99
50. Support for the green vehicle registration fee, by knowledge of transportation issues
( detailed breakdown) 100
51. Support for the flat- mileage fee, by knowledge of transportation issues
( detailed breakdown) 101
52. Support for the green mileage fee, by knowledge of transportation issues
( detailed responses) 102
53. Support for the feebate, by knowledge of transportation issues 103
54. Support for the flat- rate registration fee, by opinions on environmental policy issues
( detailed breakdown) 105
55. Support for the green vehicle registration fee, by opinions on environmental policy
issues ( detailed breakdown) 106
56. Support for the flat- mileage fee, by opinions on environmental issues
( detailed breakdown) 107
57. Support for the green mileage fee, by opinions on environmental policy issues
( detailed breakdown) 108
58. Support for the feebate, by knowledge of transportation issues ( detailed breakdown) 109
vi List of Tables
Mineta Transportation Institute
Mineta Transportation Institute
1
EXECUTIVE SUMMARY
This report explores public opinion on a new and promising concept— green transportation
taxes and fees. These are taxes and fees set at variable rates, with higher rates for more
polluting vehicles and lower rates for those that pollute less. This approach to transportation
taxes and fees adapts the traditional transportation finance system, permitting it to achieve
two critical public benefits simultaneously: encouraging drivers to choose more
environmentally- friendly transportation options, and raising revenue for needed
transportation programs.
Growing concern with global warming, air pollution, and energy security, combined with
California’s concern over shrinking transportation revenues, make this type of transportation
finance system a particularly exciting finance approach to evaluate at present. The
combination of declining transportation revenues and growing needs opens a window for
change in the transportation finance system, as lawmakers explore different options to raise
additional revenues for transportation purposes. While that window remains open, research is
needed to show whether or not green transportation taxes and fees are a politically feasible
option.
To test public support for the concept, the authors conducted a random telephone survey of
1,500 Californians, asking respondents about their support for three green transportation tax
and fee options, as well as two fees that were not structured as green ones. The questionnaire
was designed to shed light on two broad research questions:
1. How likely are California residents to support green transportation taxes and fees,
defined as those that set lower rates for more environmentally- friendly vehicles and higher
rates for less environmentally- unfriendly ones?
2. What are the socio- demographic, attitudinal, and knowledge factors that influence
support for such taxes and fees?
The survey results show that the public does indeed support the concept, and this support held
across most population subgroups.
Green Transportation Taxes and Fees— Why Now?
For decades California, like many states, has relied largely on state and federal fuel tax revenues
to fund its transportation system, supplemented with local and state sales tax and other
general fund revenues. This system no longer functions as well as it has in the past, because
lawmakers have been hesitant to raise fuel tax rates in recent decades to keep pace with
estimates of need. Although the gas tax will remain the main source of state transportation
revenues for the foreseeable future, lawmakers are interested in finding ways to supplement
those revenues. Three converging trends point to green transportation taxes and fees as a
promising approach to revising the current system:
2 Executive Summary
Mineta Transportation Institute
• A growing desire to encourage people to choose transportation behaviors and vehicles
that will reduce air pollution and greenhouse gas emissions.
• A desire to identify new sources of transportation revenue that are politically
acceptable, as well as technically desirable for other reasons.
• Increasing interest and acceptance of using market- based policies, such as tolls, to
encourage socially desirable and economically efficient transportation choices.
Survey Design
To explore the two research questions presented above, the authors conducted a random
telephone survey to test Californians’ support for the general concept of green transportation
taxes and fees. ( The survey was not designed to determine the optimal dollar charge or
implementation structure for any particular tax and fee option.)
The core of the questionnaire asked respondents to indicate their level of support or opposition
to five different transportation taxes or fees that would raise funds for maintaining and
improving highways, mass transit, and local streets. Three of these were green options, while
two were more traditional flat- rate versions of the green taxes tested. By having both flat- rate
and green versions of the two taxes, the survey could identify how support levels might vary
between the two options. The five options tested were:
• Feebate: Create a new tax and tax- rebate system on all new vehicles, based on how
much they pollute. People buying a new vehicle that doesn’t pollute much would
receive a rebate of up to $ 1,000, while people purchasing a new vehicle that pollutes a
lot would pay a tax up to $ 2,000. People who buy a vehicle average- emissions vehicles
would not pay additional fees or receive a rebate.
• Flat vehicle registration fee increase: Increase the state’s vehicle registration fee
from its then- current rate of $ 31 per vehicle per year to $ 62 per year per vehicle.
• Green vehicle registration fee increase: Increase the vehicle registration fee to an
average of $ 62 per vehicle per year, but vary the fee according how much the vehicle
pollutes. Vehicles that pollute more would pay higher fees, and vehicles that pollute
less would pay lower fees.
• Flat mileage fee: Eliminate the eighteen- cents- per- gallon state gas tax altogether and
replace it with a fee based on the number of miles driven. Each driver would pay a fee
of one cent per mile for every mile driven within the state. For example, every one
hundred miles driven would incur a fee of one dollar. Vehicles would be equipped with
an electronic means to keep track of miles driven and the fee would be paid when
drivers buy gas.
• Green mileage fee: Create a variation on the mileage fee previously described, where
the fee varies depending upon how much the vehicle pollutes. On average, vehicles
would pay one cent per mile, but vehicles that pollute the least would pay less, and
conversely, vehicles that pollute the most would pay more per mile.
Mineta Transportation Institute
Executive Summary 3
A total of 1,500 California adults were interviewed by phone from January 20 to February 1,
2008.1 Interviews were conducted in English and Spanish, and they lasted an average of 13
minutes. The telephone numbers used were a computer- generated random sample, assuring
that both listed and unlisted phones were included. The overall margin of error for the survey
is +/- 2.5% at the 95% confidence level. Results were weighted slightly to correspond to 2000
U. S. Census data for gender and region within the state.
Summary of Key Findings
The survey results show that the concept of green transportation taxes and fees strongly
appeals to Californians. The survey tested this in two ways: by testing support for three
hypothetical green transportation tax and fee policies, and also by comparing support levels for
flat- rate versus green versions of two hypothetical taxes.
Majorities of the respondents supported all three green taxes and fees tested. Even the green
mileage fee, the least popular option, had 50% support. In contrast, the green vehicle
registration fee and feebate policy both had support levels over 60%.
In addition, the survey found that respondents greatly preferred green transportation taxes and
fees to flat- rate versions. For example, when respondents were asked if they would support
increasing the vehicle registration fee from $ 31 to a flat rate of $ 62 for all vehicles, only 41%
supported the increase. In contrast, almost two- thirds of respondents ( 63%) supported a green
version of the fee, raised to an average rate of $ 62, with a higher rate for more polluting
vehicles and lower rates for less polluting vehicles. Comparing the two results shows that
converting the fee increase from a flat- rate one to a green version boosts support by 22
percentage points— from less- than- majority support to almost two- thirds support.
Respondents also preferred a green mileage fee to a flat- rate version, with 50% support for the
former but only 28% support for the latter.
The finding that Californians clearly seem to prefer green tax or fee proposals to flat- rate
versions implies that whether or not a specific green transportation tax or fee ultimately proves
popular with the public, a green version is much more likely to be popular than the traditional
approach of flat- rate taxes and fees.
Another key finding from the survey is that support for the green taxes and fees does not vary
greatly by population subgroups. The authors categorized the survey respondents into 120
subgroups— by socio- demographic characteristics, attitudes, travel behavior patterns, and so
on— and in most subgroups, support for the green registration fee and feebate policy was
above 50%. 2 For the green vehicle registration fee, 87% of the subgroups had support levels of
50% or higher, while for the feebate policy, 89% of the subgroups had support levels of 50%
or higher. Even the green mileage fee, the least popular of the three green transportation taxes
and fees tested, had a support level of at least 50% from half of the subgroups tested.
The analysis comparing support for the green and flat- rate vehicle registration fee and feebate
proposals confirms that in every subgroup more people within that subgroup supported the
4 Executive Summary
Mineta Transportation Institute
green than the flat version of the two taxes tested. There was an increase in support of at least
10 percentages points in 188 of the 193 comparisons between respondents’ support for a green
versus flat- rate transportation fee policy. For 74% of the 193 cases, the increases in support
were 20 or more percentage points. Most differences were also statistically significant.
People in a few population subgroups stood out as the least supportive of the green taxes and
fees, relative to the other subgroups in that category. Socio- demographic groupings did not
prove influential here. Rather, some of the questions about vehicle ownership, attitudes, and
knowledge revealed these low levels of support. The characteristics that proved important
were as follows:
Vehicle characteristics. People are less supportive if they:
• Drive vehicles with a fuel efficiency below 18 miles per gallon ( mpg).
• Drive pick- up trucks. ( Drivers of SUVs, vans, and minivans were also somewhat less
supportive than drivers of passenger cars, but the differences were mostly not
statistically significant.)
Opinions and attitudes. People are less supportive if they:
• Think that transportation congestion is not much of a problem or no problem for
California.
• Think that smog and air pollution are not much of a problem or no problem for
California.
• Disagree with the statement that “ We must protect the environment even if it means
paying higher prices for gasoline and electricity.”
• Think that people like themselves will have to make no changes in their lifestyle to
solve today’s environmental problems.
• Think that the U. S. should meet its growing energy needs by emphasizing gas, oil, and
coal supplies, rather than developing wind, hydro, and solar power.
• Prefer to pay lower taxes and have a state government that provides fewer services
( instead of paying higher taxes and having a state government that provides more
services).
Knowledge. People are less supportive if they:
• Think that exhaust from motor vehicles in California is definitely or probably not an
important source of the pollution that causes asthma and makes asthma attacks worse.
• Think that motor vehicles are definitely or probably not the single largest source of
greenhouse gas emissions in California.
Finally, the survey also found that respondents would be more likely to support the green
vehicle registration fee increase if the revenues were dedicated to transportation programs that
would reduce smog and greenhouse gases. Sixty- four percent of respondents said they would
be more likely to support the fee if the revenues were so used.
Mineta Transportation Institute
Executive Summary 5
Policy Implications for Transportation Professionals and Policymakers
The survey results suggest that the concept of green transportation taxes and fees is a
promising avenue of exploration. Support levels will of course vary depending on the specific
details of the tax or fee proposed, but the survey results suggest several findings and key
avenues for transportation professionals and policymakers to pursue:
1. A majority of California residents may approve at least some versions of green
transportation vehicle registration fees or feebate programs to raise new transportation
revenues.
2. California should investigate whether converting existing flat- rate transportation taxes
and fees to green versions would change behavior to help support the state’s efforts to
reduce greenhouse gas emissions.
3. To begin building public support for the concept of a mileage fee, present it with a green
rate structure.
4. To increase support for green transportation taxes and fees, educate the public about how
motor vehicle use contributes to both air pollution and global warming.
5. Public support for green transportation taxes and fees will rise if the revenues are
dedicated for programs that promote a healthy environment.
6 Executive Summary
Mineta Transportation Institute
Mineta Transportation Institute
7
INTRODUCTION
This report explores public opinion on a new and promising concept— green transportation
taxes and fees. These are taxes and fees set at variable rates, with higher rates for more
polluting vehicles and lower rates for those that pollute less. This approach to transportation
taxes and fees adapts the traditional transportation finance system to achieve two critical
public benefits at once: encouraging drivers to choose more environmentally- friendly
transportation options at the same time as raising revenue for needed transportation programs.
Growing concern with global warming, air pollution, and energy security, combined with
national concern over shrinking transportation revenues, make this type of transportation
finance system a particularly exciting finance approach to evaluate at present. The
combination of declining transportation revenues and growing needs opens a window for
change in the transportation finance system, as lawmakers explore different options to raise
additional revenues for transportation purposes. While that window remains open, research is
needed to show whether or not green transportation taxes and fees are a politically feasible
option.
To date, states have rarely used or even seriously evaluated the potential for green
transportation taxes and fees, but in the last few years, interest in the concept has appeared at
the margins of main- stream policy debates. To test public support for the concept, the authors
conducted a random telephone survey of 1,500 Californians, asking them about their support
for three green transportation tax and fee options, as well as two fees that were not structured
as green ones. The survey results show that the public does indeed support the concept. The
time is right for transportation policy makers to follow their constituents and explore how
green transportation taxes and fees could best be integrated into the current finance system.
Green Transportation Taxes and Fees– Why Now?
Like many states, for decades California has relied largely on state and federal fuel tax revenues
to fund its transportation system, supplemented with local and state sales tax and other
general fund revenues. This system no longer functions as well as it has in the past, because
lawmakers have been hesitant to raise fuel tax rates in recent decades to keep revenues in pace
with estimates of need. Although the gas tax will remain the main source of state
transportation revenues for the foreseeable future, lawmakers are interested in finding ways to
supplement those revenues. Three converging trends point to green transportation taxes and
fees as a promising approach to revising the current system:
• A growing desire to encourage people to choose transportation behaviors and vehicles
that will reduce air pollution and greenhouse gas emissions.
• A desire to identify new sources of transportation revenue that are politically
acceptable, as well as technically desirable for other reasons.
8 Introduction
Mineta Transportation Institute
• Increasing interest and acceptance of using market- based policies, such as tolls, to
encourage socially desirable transportation choices.
Reducing the Impact of the Transportation System on the Environment
Worries about air pollution and global warming— not to mention public concern over energy
security and rising fuel prices— have created an unprecedented level of public interest in
finding ways to improve fuel efficiency, develop non- petroleum- based fuels, and reduce
emissions. Much of the attention has focused on new vehicle and fuel technologies. To a more
limited extent, there is also growing interest in reducing travel demand by providing residents
with alternatives to solo driving, whether that be reliable and convenient transit service, or
safe walking and biking facilities. If green transportation taxes and fees were adopted, they
could encourage drivers to choose more fuel- efficient and lower polluting vehicles. The finance
system could thus be one part of the solution to the air quality and global warming problems.
The state’s residents have long been at least somewhat aware of the connection between motor
vehicle use and environmental quality because of a long history of poor air quality in most
urban areas. Although by some measures air quality has improved markedly over the past
decades as vehicle technologies have improved, the even- increasing number of miles driven per
year in the state has to some extent counteracted technology- related improvements and kept
air quality problems in public view. Further, recent research has revealed new and more serious
health risks associated with air pollution, especially fine particulate emissions, making even
low levels of pollution worrisome.
In the last decade, the accumulating scientific evidence about global warming trends and the
likely impacts on human health, the environment and economy have become matters of
widespread public discussion and concern. The resulting publicity has educated Californians
about this additional problem linked to motor vehicle use. Al Gore’s 2006 film An Inconvenient
Truth, as well as the 2007 Nobel Peace Prize subsequently granted to Gore and the United
Nation’s Intergovernmental Panel on Climate Change, brought the global warming threat
squarely into public view. Also, in recent years state policy makers have passed a series of
widely publicized measures to reduce greenhouse gas emissions, further focusing public
interest on climate change and the role played by motor vehicle use.
The Need for New Sources of Transportation Revenue
Now is a critical time to assess whether or not the public would support green taxes and fees
for transportation, because states from California to New Hampshire are in the process of
revisiting their transportation finance systems. States face a growing challenge to fund their
transportation systems as the traditional source of revenue— state and federal gas taxes— has
declined substantially in real ( inflation- adjusted) terms.
Transportation professionals and elected officials are intensely interested finding new revenues
to both maintain and expand their transportation systems, for numerous reasons. Much of the
national highway system is reaching an age where major— and expensive— rehabilitation is
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Introduction 9
needed. At the same time, expected population growth and development in new areas will
create demand for new transportation infrastructure and services, whether to accommodate
more traffic in existing communities, or to lay out infrastructure in newly developed areas.
There is also increasing interest in providing efficient transit service, to offer residents a sound
alternative to driving, but in most communities that would require considerable revenue to
support both capital projects and operations. A final factor raising costs is that construction
costs have risen more rapidly than general inflation in recent years, a trend that may well
continue. ( The American Association of State Highway and Transportation Officials
[ AASHTO] predicts a 70% increase in construction costs between 1993 and 2015.3)
Despite these many reasons that policymakers may wish to increase transportation system
expenditures, available revenues are not keeping pace. For decades, state and federal fuel taxes
served as the main source of the transportation finance system. However, the buying power
from fuel tax receipts is falling far short of local and state spending desires, and this trend will
likely continue into the future, for two key reasons. One factor likely to reduce available
revenues is that the fuel tax is currently levied as a pennies- per- gallon charge, so inflation
quickly begins to eat away at the buying power of the revenues unless the rate is regularly
raised. In almost all states and at the federal level, the rate can be raised only through direct
action by legislators, and elected officials have shown little enthusiasm for raising fuel tax rates
in the last decade. 4 A second factor that makes fuel taxes unlikely to keep pace with future
needs is that consumers are expected to shift toward more fuel efficient vehicles or vehicles
running on fuels other than gasoline or diesel. Unless significant changes are made to the
current fuel tax system, these trends would reduce receipts relative to use of the road system.
The combination of rising expenditure desires and shrinking fuel tax revenues leaves
transportation professionals in a quandary. One approach to the problem may be to make
expenditures more efficient, yet there is also widespread desire to find additional revenues. In
fact, among transportation professionals and the transportation industry itself, there is
near- unanimous consensus that additional revenues are required. However, in most cases state
legislatures have recently been unwilling to raise fuel tax rates. Consequently, state and local
policy makers have explored alternative sources of revenue, including sales taxes, tolling, and
development fees. There is also mild interest in replacing fuel taxes with mileage- based fees,
though the general consensus among finance experts is that a mileage fee will not be
implemented in the short or even, probably, the medium term. 5
Choosing the right alternative finance mechanisms to pursue is tricky. For example, policy
makers look for options that raise sufficient revenues, are inexpensive and simple to
administer, and are equitable to different population sub- groups. In addition to these goals,
political acceptability is critical. Not only must legislators themselves be willing to support
new finance approaches, they must be convinced that the public will support them as well. As
another outcome of legislative reluctance to raise fees and taxes that generate transportation
revenues, elected officials in California have put many potential revenue measures before the
voters as ballot propositions. Thus, if green transportation taxes and fees are to be seriously
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considered in the current political climate, knowing how the public perceives them is an
essential component of assessing their feasibility. And if they prove popular with the public,
then green transportation taxes and fees will be of great interest to transportation professionals
and policy makers.
Green Transportation Finance and the Current Trend Toward Market- Based Policies
to Improve the Transportation System
A final trend in transportation finance that meshes well with the green transportation finance
concept is the modest but growing interest among policy makers in choosing finance
mechanisms that provide users incentives to make socially optimal travel choices. One option
is to use pricing to encourage drivers to shift trips to off- peak hours as a way to reduce traffic
congestion. This option is often referred to as “ congestion pricing” or “ value pricing.” Green
transportation taxes and fees use market- based pricing to encourage another socially desirable
outcome: travel choices that have a lower impact on the environment, particularly emissions of
air pollutants.
In countries outside the U. S., there has been some history of charging higher fees for more
polluting or fuel- inefficient vehicles. For example, the Canadian province of Quebec charges
higher vehicle registration fees based upon the size of the engine, and Ontario has a “ tax for
fuel conservation” that applies to new vehicles. A 2007 review of vehicle taxation in European
countries identified eight countries that base their vehicle registration fee rate at least in part
on some measure of environmental impact, whether fuel economy or emissions. 6
In England, a few local jurisdictions have begun to charge higher fees for resident parking
permits for high- emission vehicles. For example, in Richmond- upon- Thames, high- emission
cars pay as much as three times the permit price as low- emission vehicles. 7 Finally, a few cities
have considered high- profile congestion fees that vary according to vehicle emissions. In 2007,
London officials announced plans to charge vehicles with the highest CO2 emissions a fee of
£ 25 a day ( about $ 50 U. S.) to enter the city’s congestion charging zone, compared to an £ 8 fee
for other vehicles. However, this plan was put on hold in 2008 with the election of a new
mayor. In January 2008, the city of Milan, Italy introduced a trial congestion- pricing program
whereby vehicles pay a fee to enter the congested area, and the fee varies from € 2 to € 10,
depending on the vehicle’s pollution rating. Vehicles with the very lowest emissions rates,
such as electric powered cars and scooters, pay no fee at all. 8
In the U. S., the use of market- based policies to reduce consumption and indirectly address
environmental externalities has some history, though much of it relates to products and
services outside the transportation sector. For example, fees that vary based upon the
magnitude of people’s environmental impacts have been implemented to address municipal
solid waste generation ( for example, pay- by- the- bag collection charges, advanced disposal fees,
and so on) and water management ( for example, meter rate pricing). The advantage of these
market- based policies is that environmental improvements can be achieved at a lower societal
cost than with traditional command- and- control approaches. In addition, they are in line with
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Introduction 11
the “ polluter- pays” principle; if fees are set at the appropriate level, individuals pay for the
environmental harm they make based on their choices.
There has been considerable research in the United States on market- based pricing to manage
traffic congestion and parking shortages, but little research or policy activity has looked at
charging different rates for different vehicles or other transportation services specifically to
account for varying levels of environmental externalities. Moreover, there are only a few
examples of such taxes or fees being adopted in the U. S. The federal “ gas guzzler” tax on new
cars is one example, though it is paid by the manufacturer and only applies to new cars, not
trucks or SUVs. More popular than taxes or fees have been tax credits or other financial benefits
to purchasers of hybrid vehicles. The federal government has offered tax credits to purchasers
of some new hybrid vehicles, and some states have also offered tax credits. A few cities have
waived parking fees in city- owned facilities for all- electric vehicles. 9
Since 2007, the California legislature has shown a few stirrings of interest regarding green
transportation finance measures that extend past measures to promote electric- hybrid vehicles.
Several different bills have been introduced, though so far none have been passed into law. In
February 2007, Assemblymember Ira Ruskin introduced AB 493, a bill to create a feebate
system for new car purchases whereby the fees and rebates would be set according to the
vehicle’s carbon emissions. This bill died a year later. In February 2008, Assemblymember
Mike Feuer introduced a bill to allowed the Los Angeles County Transportation Authority to
impose a separate vehicle registration fee, with the rate linked to the vehicle’s carbon
emissions. In the same month, Assemblymember Feuer introduced a separate bill, AB 2388,
that would have imposed additional statewide vehicle registration fees, with the fees varying
by both the vehicle’s weight and carbon emissions.
Overview of the Research Methods
This study was designed to shed light on two broad research questions:
1. How likely are California residents to support green transportation taxes and fees,
defined as taxes and fees that set lower rates for more environmentally- friendly vehicles and
higher rates for less environmentally- unfriendly ones?
2. What are the socio- demographic, attitudinal, and knowledge factors that influence
support for such taxes and fees?
To explore these two questions, the authors conducted a random telephone survey of 1,500
Californians that tested their support for the general concept of green transportation taxes and
fees. Neither the study nor the survey was not designed to determine the optimal dollar charge
or implementation structure for any particular tax and fee option.
The survey questionnaire was designed after a review of public opinion polls on the topic of
transportation finance and also the research literature available on the topics of ( 1) public
opinion about transportation finance, and ( 2) the factors that tend to correlate with
pro- environmental behavior. This literature review generated ideas about what types of fee
12 Introduction
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mechanisms had not yet been well- tested, how to identify general political views and policy
positions likely to predict support for green finance policies, and options for specific ways to
word questions.
The core of the questionnaire asked respondents to indicate their level of support or opposition
to five different transportation taxes or fees that would raise funds for maintaining and
improving highways, mass transit, and local streets. Three of these were green options, while
two were more traditional flat- rate versions of the green taxes tested. By having both flat- rate
and green versions of the two taxes, the survey could identify how support levels might vary
between the two options. The five options tested were:
• Feebate: Create a new tax and tax- rebate system on all new vehicles, based on how
much they pollute. People buying a new vehicle that doesn’t pollute much would
receive a rebate of up to $ 1,000, while people purchasing a new vehicle that pollutes a
lot would pay a tax up to $ 2,000. People who buy an average- emission vehicle would
not pay additional fees or receive a rebate.
• Flat vehicle registration fee increase: Increase the state's vehicle registration fee
from its then- current rate of $ 31 per vehicle per year to $ 62 per year per vehicle.
• Green vehicle registration fee increase: Increase the vehicle registration fee to an
average of $ 62 per vehicle per year, but vary the fee according to the amount of the
vehicle’s emissions. Vehicles that pollute more would pay higher fees, and lower
emissions vehicles would pay lower fees.
• Flat mileage fee: Eliminate the eighteen- cents- per- gallon state gas tax altogether and
replace it with a fee based on the number of miles driven. Each driver would pay a fee
of one cent per mile for every mile driven within the state. For example, every one
hundred miles driven would incur a fee of one dollar. Vehicles would be equipped with
an electronic means to keep track of miles driven and the fee would be paid when
drivers buy gas.
• Green mileage fee: Create a variation on the mileage fee previously described, where
the fee varies depending upon how much the vehicle pollutes. On average, vehicles
would pay one cent per mile, but vehicles that pollute the least would pay less and
vehicles that pollute the most would pay more per mile.
This selection of measures therefore covered three different transactions: ( 1) When a person
purchases a new vehicle; ( 2) when owners register their vehicle annually; and ( 3) when drivers
purchase fuel. The resulting survey data was analyzed to identify those particular subgroups of
the population who were more or less likely to support green transportation tax and fee
options.
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Introduction 13
Overview of Report Contents
The next chapter in this report, “ Findings from the Literature,” discusses the existing survey
data on public opinion about green transportation finance, as well as the broader literature on
the factors likely to predict pro- environmental behavior. The chapters titled “ Survey Design
and Administration,” and “ Survey Results,” describe the survey design and administration,
and then the survey results. The final chapter, “ Conclusions and Recommendations,” discusses
key policy implications that can be taken from the survey results. The report’s appendixes
present the survey questionnaire and top- line results, as well as a detailed set of tables showing
support for the five policies among different socio- demographic, attitudinal, knowledge, and
other subgroups of the population.
14 Introduction
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15
FINDINGS FROM THE LITERATURE
The research project began with an extensive review of public polling results and literature
related to the two project research questions. This chapter is structured around literature
relating to each of those questions. For the first research question, “ How likely are Californians
to support green transportation taxes and fees?” the authors examined the literature on public
support for transportation taxes and fees that were in some way described to respondents as
having a connection with environmental protection. To better understand the second question,
“ What are the socio- demographic, attitudinal, and knowledge factors that influence support
for such taxes and fees?” the authors looked much more broadly at research investigating the
demographic, attitudinal, and knowledge factors correlated with pro- environment behavior in
general, especially willingness to pay for “ green” products and services.
To identify relevant research and public opinion polls the authors relied on several search
strategies. The first was a review of databases and catalogues to identify published, academic
literature related to public opinions on transportation finance, as well as public reaction to
other “ green” policies such as recycling or renewable electricity generation. The bibliographies
of these items often proved fruitful sources of additional information. Finally, extensive
internet research identified various public opinion polls related to transportation finance that
had not been formally published or had appeared in non- academic sources. Cumulatively,
these various methods produced well over a hundred reports and studies.
This review was used to map out the existing state of knowledge about public opinions on
these topics, as well as to generate ideas for developing the questionnaire used in the public
opinion poll later conducted.
TRANSPORTATION FINANCE MEASURES LINKED TO ENVIRONMENTAL
OUTCOMES: A REVIEW OF PUBLIC OPINION
There has been a fairly wide range of polling on transportation finance topics in the last
decade, though relatively few polls have asked about finance options with some environmental
connection. Most common are polls asking respondents how they would respond to specific
transportation tax and fee proposals. These polls are most often conducted by interest groups
and government agencies that are either creating, or in the process of supporting or opposing,
finance measures that have been put before the voters as local or state referendums. Supporters
of such referendums often conduct public opinion polls while crafting ballot proposals. Later,
once a proposition is on the ballot, further polling is often conducted by supporters,
opponents, and the media.
The volume of such polling has increased in the last decades because states and local
governments have moved away from relying on traditional sources such as the state and federal
gas tax, instead proposing alternative funding sources as voter referendums. In California,
16 Findings from the Literature
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there have been dozens of county- wide transportation sales tax measures, and these have
generated the most polling.
However, these election- targeted polls are not the only source of public opinion data on
transportation finance topics. From time to time the media includes transportation finance
questions in public opinion polls on current issues, and interest groups like the Automobile
Clubs of America or environmental advocacy groups sometimes include transportation finance
questions when polling their members or the general public. Within California, the Public
Policy Institute of California regularly surveys the public on policy issues, and these polls
sometimes include at least a question or two related to transportation finance options. Finally,
there are also a handful of polls on transportation finance that have been conducted by
academic research organizations or nonpartisan research groups. Although these surveys are
sometimes undertaken on behalf of a government agency funding the work, the studies are not
directly linked to an active political campaign.
Many of the surveys, especially those undertaken as part of crafting or promoting a specific
ballot proposal, ask only about a particular transportation tax, such as a sales tax or regional
gas tax supplement. However, a few of the surveys, especially those undertaken by researchers
or policy research organizations, examine a variety of options. 10
The type of analysis conducted on the survey results varies considerably, but many of the
available surveys often report only basic response frequencies, without looking at support by
many population subgroups. The political polls may break out results by geographic region or
political party, but often not by many other categories. Some polls, however, especially those
by research groups, are more likely to look at a wider range of socio- demographic and other
population groups. 11A few of the polls also look at how support levels correlate with attitudes
or knowledge about various policy issues, but this analysis is relatively sparse. Finally, a few of
the published studies build regression models to predict support based on a range of
variables. 12
As mentioned above, relatively few of the public opinion polls testing public support for
different transportation measures mention to respondents how the finance options might
impact environmental quality. However, there are some exceptions. Several polls broadly asked
if respondents supported increasing a transportation- related tax in order to help address an
environmental problem. A sample of these polls appears in Table 1. In these polls, the tax did
not vary based on the pollution level of the vehicle, in contrast to the “ green” or environmental
taxes addressed in this research. The findings from the polls vary significantly, as does the
question wording and framing. Some polls found majority support for increasing gas or
vehicle taxes to address global warming, though the most recent national poll the authors
found, conducted in April 2007, found only 38% favored increasing the federal gas tax to
address global warming.
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Findings from the Literature 17
Several polls did ask about taxes or fees that varied based upon the environmental impacts of
the vehicle. Table 2 summarizes all of the polls found. Again, findings varied and may be
dependent upon the exact question asked. For example, the lowest level of support was from a
poll that asked people13 to choose between four options. In this case, nearly half of respondents
supported regulation, while only 11% favored higher taxes on less efficient vehicles. The other
polls did not ask respondents to choose between different options and generally had higher
levels of support for the taxes and fees in question. The polls with the highest levels of support
did not include a specific tax or fee amount.
Table 1 Findings from a sample on flat transportation taxes to improve the environment
Organization/ Source Date of Survey Location Findings
ABC News/ Washington
Post/ Stanford University 2007 U. S. 32% favor increasing gas taxes “ so people
either drive less, or buy cars that use less gas”
CBS News/ New York Times 2007 U. S. 38% favor increasing federal gas tax to reduce
energy consumption and global warming
Metropolitan Transportation
Commission 2007
San
Francisco
Bay Area
69% would consider a 25 cent per gallon gas tax
if it was used to reduce global warming
New York Times 2006 U. S.
55% of adults supported an increase in the gas
tax if it reduced dependence on foreign oil, and
59% supported an increase if it reduced global
warming. In contrast, 85% opposed an increase
if it was presented without any direct outcomes
Fairbank, Maslin, Maullin &
Associates 2006 California
58% supported a one cent increase in the gas
tax to fund technology to reduce oil dependence
and promote alternative fuels.
National Renewable Energy
Laboratory 1998 U. S.
70% preferred a 3% tax on new vehicles if the
nation determined that it was important to
reduce greenhouse gases, compared to 17%
preferring 25 cent per gallon gas tax
Pew Research Center for the
People & the Press 1997 U. S.
73% of adults were willing to pay 5 cents more
per gallon of gasoline ‘‘ if it would significantly
reduce global warming’’
Sources: ABC News/ Washington Post/ Stanford University, “ Concern Soars About Global Warming As
World’s Top Environmental Threat,” April 20, 2007,
http:// woods. stanford. edu/ docs/ surveys/ GW_ 2007_ ABC_ News_ Release. pdf ( accessed on July 20, 2008);
CBS News/ New York Times, “ Americans’ Views on the Environment,” April 26, 2007,
http:// www. cbsnews. com/ htdocs/ pdf/ 042607environment. pdf ( accessed on July 20, 2008); BW Research
Partnership, “ Transportation 2035 Survey Results” presented to MTC Planning Committee, November 9,
2007, http:// www. mtc. ca. gov/ planning/ 2035_ plan/ 2035_ poll_ results. ppt ( accessed on July 20, 2008; L.
Uchitelle, and M. Thee, “ Americans are cautiously open to gas tax rise, poll shows,” New York Times,
February 28, 2006, p. 14; Fairbank, Maslin, Maullin & Associates, “ California Statewide Survey
220- 1985WT Final,” February 2006; T. Gurikova, and S. C. Davis, Transportation Energy Survey Data Book
1.1, Oak Ridge National Laboratory, ORNL/ SUB/ 02- 4000008627/ 01, May 2002,
http:// www- cta. ornl. gov/ cta/ Publications/ Reports/ ORNL_ SUB_ 02- 4000008627_ 01. pdf ( accessed on July
20, 2008); Pew Research Center for the People & the Press, “ November 1997 News Interest Index -- Final
Topline” ( Princeton, New Jersey, 1997), http:// people- press. org/ reports/ print. php3? PageID= 490 [ accessed
on August 22, 2006]; Gurikova, T. and Davis, S. C., Transportation Energy Survey Data Book 1.1, Oak Ridge
National Laboratory, ORNL/ SUB/ 02- 4000008627/ 01, May 2002,
http:// www- cta. ornl. gov/ cta/ Publications/ Reports/ ORNL_ SUB_ 02- 4000008627_ 01. pdf ( accessed on July
20, 2008).
18 Findings from the Literature
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Table 2 Findings from surveys on variable environmental taxes or fees for transportation
Organization/ Source Date of Survey Location Findings
YouGov 2008 London,
England
41% supported increasing the congestion charge to £ 25 for
higher polluting cars.
Fairbank, Maslin, Maullin
& Associates 2007 Los Angeles
County, CA
45% supported a fee of one cent per pound of CO2 emitted
by a vehicle, averaging $ 22 per year instead of a one- half
cent sales tax increase
Mineta Transportation
Institute 2006 California 63% of likely voters supported the idea of annual vehicle
registration fees that are higher for more polluting vehicles
Fairbank, Maslin, Maullin
& Associates 2006 California
62% supported charging a fee on new vehicles that emitted
a large amount of global warming pollutants.
60% supported a “ feebate” program ( rebates for cleanest
cars, fees for most polluting cars, ranging from $ 200 to
$ 2500).
ABC News/ Time
Magazine/ Washington
Post
2005 United States
54% supported allowing single drivers in hybrid cars to use
HOV lanes for free to encourage use of hybrids, compared
to 36% supporting single drivers paying a toll to use the
HOV lanes
Kockelman, Podgorski, et
al. 2003 Texas
73% of Texas residents thought that charging higher tolls
for larger, heavier, or higher polluting vehicles was a good
idea
Washington State
Department of
Transportation
2004 Washington 42% of voters expressed support for a tax based on a car’s
weight
Public Policy Institute of
California ( PPIC) 2003 California 81% favor tax breaks to encourage the purchase of hybrid
and electric vehicles
National Renewable
Energy Laboratory 2001 United States
11% supported higher taxes on less efficient vehicles to
reduce dependence on imported oil, given four choices.
Greatest level of support ( 48%) for regulation to make
vehicles more efficient. 6% supported higher fuel taxes.
Southern California
Association of
Governments ( cited in
Krupnick, et al.)
1996
Southern
California
( five counties)
39% supported a mileage fee ranging from 1- 5 cents per
mile depending upon the vehicle emissions. Support
increased to almost 50% when respondents were told that
most revenues would be returned to taxpayers through
reduced fees or coupons.
J. Moore Methods ( cited
in Krupnick, et al.) 1994
Southern
California
( four
counties)
51% supported a fee based upon vehicle’s pollution level,
with revenues used to help improve air quality
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Findings from the Literature 19
FACTORS CORRELATED WITH PRO- ENVIRONMENT BEHAVIOR
Studies from the applied behavior and environmental psychology literatures that focus on
pro- environmental behavior ( PEB) were influential for our research. Several theories have been
proposed to explain the relationship between individual attitudes and values and PEB,
including Ajzen’s Theory of Planned Behavior, Schwartz’s Norm- Activation Model, and
Dunlap and Van Liere’s New Environmental/ Ecological Paradigm. 14 These theories all stress
that individual environmental attitudes can help predict PEB to some extent.
Very few of the polls listed in Table 1 and Table 2 provided analyses that explain support for
environmental taxes or fees in terms of respondent characteristics. In the handful of exceptions,
more emphasis was placed on demographics than the environmental attitudes or values
emphasized in the theories explaining PEB. The exceptions include Krupnick et al.’ s study of
a mileage fee in Southern California that varied with emissions, 15 Dill and Weinstein’s analysis
of a variable registration fee in California, 16 and the poll of Londoners regarding the higher
congestion pricing for more polluting vehicles. 17 The first two studies used multivariate
analysis to examine the relationships. All three studies found that support for green
transportation fees declined with the respondent’s age. The studies were not consistent with
respect to findings on gender, however, with one finding more support among women, one
more support among men, and one finding no difference. As for ethnicity, findings from
Krupnick, et al. and Dill and Weinstein suggest that Asians and Hispanics may be
particularly supportive of green transportation fees. Contrary to their hypothesis, Krupnick et
Sources: YouGov, “ YouGov/ Evening Standard Survey Results, Fieldwork: 20th – 25th March 2008,”
http:// i. thisislondon. co. uk/ i/ pix/ 2008/ 03/ mayorsurvey. pdf ( accessed on July 20, 2008); Fairbank, Maslin,
Maullin & Associates, “ Los Angeles County Transportation Ballot Measure Survey 2007”; Asha Weinstein,
Jennifer Dill, Todd Goldman, John Hall, Franziska Holtzman, Joe Recker, and Eileen Goodwin, Transportation
Financing Opportunities for the State of California ( San Jose, CA: Mineta Transportation Institute, College
of Business, San Jose State University, October 2006),
http:// transweb. sjsu. edu/ mtiportal/ research/ publications/ documents/ 06- 01/ TransportFinanceOpps5_ 0201
07. pdf ( accessed on July 5, 2008); Fairbank, Maslin, Maullin & Associates, “ California Statewide Survey
220- 1985WT Final,” February 2006; ABC News/ Time Magazine/ Washington Post, “ A Look Under the
Hood of a Nation on Wheels: ABC News/ Time Magazine/ Washington Post Poll” ( 2005),
http:// abcnews. go. com/ images/ Politics/ 973a2Traffic. pdf ( accessed on August 22, 2006); K. M. Kockelman,
K. V. Podgorski, M. Bina, and S. Gadda, “ Public Perceptions of Pricing Existing Roads and Other
Transportation Policies: The Texas Perspective,” paper presented at the 85th Annual Meeting of the
Transportation Research Board, Washington DC, January 2006; Washington State Department of
Transportation, “ 2004 Focus Group Results” ( 2004),
http:// www. wsdot. wa. gov/ Accountability/ PublicOpinion ( accessed on August 22, 2006); Mark Baldassare,
“ PPIC Statewide Survey: Special Survey on Californians and the Environment” ( San Francisco: Public Policy
Institute of California, July 2003), http:// www. ppic. org/ content/ pubs/ survey/ S_ 703MBS. pdf ( accessed on
July 20, 2008); T. Gurikova, and S. C. Davis, Transportation Energy Survey Data Book 1.1,
ORNL/ SUB/ 02- 4000008627/ 01, ( Oak Ridge National Laboratory, May 2002),
http:// www- cta. ornl. gov/ cta/ Publications/ Reports/ ORNL_ SUB_ 02- 4000008627_ 01. pdf ( accessed on July
20, 2008); Alan Krupnick, Winston Harrington, and Anna Alberini, “ Public Support for Pollution Fee Policies
for Motor Vehicles with Revenue Recycling: Survey Results,” Regional Science and Urban Economics 31, no.
4 ( 2001), 505- 22; J. Moore Methods, Inc. Southern California Congestion Pricing Study, various survey
versions, 1994, as cited in Krupnick, Harrington, and Alberini, ibid.
20 Findings from the Literature
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al found higher support among people with less education. Dill and Weinstein found that
lower- income adults were more likely than other income groups to oppose a flat- rate
registration fee increase but support a green version of the fee increase.
None of these studies examined how knowledge of environmental issues influenced opinions.
However, all three did look at political affiliation and/ or attitudes in some manner. Not
surprising, all three studies found lower levels of support among conservatives or Republicans.
Krupnick et al. found that support was positively correlated with how much air pollution
affected the respondent and whether respondents felt drivers ( in general) would change their
behavior in response to the fee. 18 Dill and Weinstein found that people who were transit users
and people who wanted to focus transportation spending on transit were particularly
supportive of the green fee option, even after controlling for income. The findings from these
two studies may indirectly reflect environmental values that were not specifically asked about
in the survey. In addition, Dill and Weinstein found that people who thought taxes were too
high opposed raising registration fees, but that their level of opposition diminished with the
green option compared to a flat fee increase. 19
Given the lack of literature examining factors related to PEB and support for green
transportation taxes and fees, it is useful to look to other transportation and consumer
behaviors. For decades, travel behavior research has examined the role of demographics,
particularly income, on mode choice, including those modes which could be labeled PEB ( for
example, transit, bicycling, and walking). More recently, several travel behavior studies have
found that attitudes are significantly correlated with the amount of driving or walking. 20
Kitamura et al. found that people with pro- environment attitudes made a significantly smaller
share of their trips by car. 21 In a study of Australian college students, individual values and
beliefs about the environmental impact of motor vehicles were strong predictors of a travel
mode shift to public transit. 22 Similarly, Coogan, Karash, Adler, and Sallis found a significant
relationship between personal values and walking as a primary transportation mode choice. 23
Very few studies look at both knowledge and attitudes. One that does is a survey of
Sacramento, CA, area residents by Flamm, who examined the relationship between both
environmental knowledge and attitudes and travel and vehicle decisions. 24 His key findings
were as follows:
1) environmental knowledge is directly related to household ownership
of more fuel efficient vehicles and inversely related to estimated annual
household fuel consumption, 2) environmental attitudes are directly
related to household ownership of more fuel efficient vehicles and
inversely related to number of household vehicles, estimated annual
household miles driven, and estimated annual household fuel
consumption, 3) vehicle ownership and use affect environmental
attitudes to a small degree ( though much less than attitudes affect
vehicle ownership and use), but do not affect environmental knowledge
at all, 4) environmental knowledge and environmental attitudes are
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Findings from the Literature 21
strongly related, and 5) people perceive barriers to making their vehicle
ownership and use more closely reflect their attitudes and knowledge
and can identify ways in which car manufacturers and elected officials
might facilitate more environmentally responsible vehicle ownership
and use decisions. 25
A growing number of studies apply the “ Theory of Planned Behavior” to travel decisions,
particularly to driving and decisions to reduce car use. A meta- review of 23 studies found that
attitudes toward car use had a moderate effect on driving, and that attitudes toward non- car
modes ( for example, transit, walking, or bicycling) often had a larger effect. Findings
regarding the effect of “ subjective norms,” or the respondents’ perception of social approval for
the behavior, were less conclusive. 26 The authors concluded there was only weak evidence to
show a link between four pro- environment variables and driving. 27 However, two of the
studies examined found that the extent to which drivers felt responsible for the environmental
effects of car use had a small to medium effect on behavior. A more recent study applying the
Theory of Planned Behavior to transportation mode decisions classified individuals into six
distinct groups: four car- owning and two non- car- owning. 28 For one group of non- car owners,
environmental values were the primary reason for choosing alternate travel modes. Even
among one group of car owners, the “ Aspiring Environmentalists,” environmental attitudes
were key reasons why they had significantly reduced their vehicle use.
Several studies have explored the reasons why people choose to drive “ green” vehicles, such as
hybrids or clean- fuel vehicles. 29 Across most of these studies, a key barrier preventing
consumers from adopting “ green” vehicles related to vehicle performance ( actual or perceived).
According to Ewing and Sarigollu, even though consumers may hold strong
pro- environmental attitudes, they were unwilling to make the trade- off between
environmental benefits and poorer vehicle performance ( for example, in terms of range,
acceleration, or refueling time for electric vehicles). 30 Kahn proxies for environmental
attitudes using affiliation with the Green Party in California, and finds that communities with
a larger percentage of registered Greens are more likely to purchase hybrid vehicles. 31 The role
of socio- demographic characteristics as predictors of demand for clean vehicles among
residents of Hamilton, Ontario, was also explored by Potoglou and Kanaraglou. 32 The authors
found that women, higher income individuals, younger adults, and those with higher
education levels were more likely to choose environmentally- friendly vehicles.
Of particular interest to our research are studies exploring consumer willingness to pay for
“ green” products. Willingness to pay for green products of many types has been widely
studied, although not often with regard to transportation. The underlying premise behind this
research is that consumers make certain trade- offs among product attributes, including cost
and environmental quality. Although there is limited empirical evidence that specifically
examines individuals’ support for green transportation taxes and fees, there is significant
evidence to suggest that consumers’ willingness to pay for one green product is likely to reflect
a preference for other environmentally- friendly behaviors. 33 Thus, it is reasonable to expect
22 Findings from the Literature
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that the factors influencing willingness to pay for environmentally- friendly products such as
green electricity or organic foods would be similar to the factors linked with support for green
transportation taxes. Laroche, Bergeron, and Barbaro- Forleo conducted an extensive literature
review and identified five major factors that influence willingness to pay for green products:
socio- demographic characteristics, environmental knowledge, environmental attitudes,
individual values, and environmental behaviors. 34
Numerous studies have attempted to develop a typical green consumer profile, yet often these
profiles conflict. 35 In general, significant demographic predictors include age, education,
income, and gender. For example, several studies find that older adults are less likely to
support higher prices for green products. 36 Some studies also find that education levels are
positively correlated with willingness to pay for green products. This relationship is noted
across a diverse range of products including green electricity programs, 37 organic and locally
produced food, 38 environmentally friendly cars, 39 and certified forest products. 40 Similarly,
income also tends to be positively correlated with willingness to pay. 41 Finally, gender is often
found to influence willingness to pay, with women more likely to pay higher prices than men,
particularly where there is a strong perception of the connection between the “ green” product
and health, such as with organic food. 42
Although the majority of studies focus on demographic characteristics, these are often not the
most important predictors of willingness to pay. Factors such as environmental attitudes,
individual values, and knowledge about environmental issues are frequently more important
predictors. 43 For example, one study found that participation in green electricity programs in
Japan was strongly influenced by environmental knowledge and, although financial
considerations are the driving factors, knowledge was found to be a factor for willingness to
pay for a ( green) fuel cell taxi in London. 44 Interestingly, altruistic reasons were shown to
outweigh financial considerations in a study of corporate participation in green energy
programs. 45 Similarly, research has found that consumer preferences for organic food are
strongly influenced by attitudes toward the environment and personal values. 46
It may be that few studies include attitudes and knowledge because gathering such data is
more complex and adds to survey costs. However, it is likely that many of the correlations
found between demographics and behavior are actually detecting a correlation between
demographics and attitudes, which then influence behavior. Sorting out the relative influence
of knowledge, attitudes, and demographics in determining behavior or support for green
transportation finance options has important policy implications. For example, if knowledge
and attitudes are the most important factors, then there may be a role for public education
campaigns as part of a strategy to build public support for green transportation taxes and fees.
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23
SURVEY DESIGN AND ADMINISTRATION
The survey was designed primarily to explore Californians’ support for the concept of green
transportation taxes and fees, where the rate varies according to the environmental
performance of the vehicles. The survey was not designed to assess support of any particular
tax and fee option that has been proposed by policy makers or interest groups. The objective
was to test whether Californians support the general concept of green taxes and fees, though
specific dollar amounts were included to make the decision more realistic for respondents. A
secondary goal was to identify subgroups within the population who might be more or less
likely to support the concept.
This chapter discusses the design of the questionnaire and the survey data collection
procedures.
Questionnaire Design
The survey questionnaire was designed after the review of public opinion polls on the topic of
transportation finance, which was discussed in the previous chapter. These polls were used to
generate ideas about what types of fee mechanisms had not yet been well tested, how to
identify general political views and policy positions on issues related to green transportation
finance, and options for specific ways to word questions. 47
The core of the questionnaire asked respondents to indicate their level of support or opposition
for five different types of transportation tax and fee options to raise funds for maintaining and
improving highways, mass transit, and local streets. Three of these were green options, while
two were more traditional flat- rate versions of the green taxes tested. By having both flat- rate
and green versions of the two taxes, the survey could identify how support levels might vary
between the two options. For each option, respondents were asked if they would “ strongly
support, somewhat support, somewhat oppose, or strongly oppose” that idea. The five options
tested were:
• Feebate: Create a new tax and tax rebate system on all new vehicles based on how
much they pollute. People who buy a new vehicle that doesn't pollute much would
receive a rebate of up to $ 1,000. People who buy a new vehicle that pollutes a lot, such
as a very large SUV, would pay a tax up to $ 2,000. People who buy a vehicle that
pollutes about the average would not pay or receive anything.
• Flat vehicle registration fee increase: Increase the state’s vehicle registration fee
from its then- current rate of $ 31 per vehicle per year to $ 62 per year per vehicle.
• Green vehicle registration fee increase: Increase the vehicle registration fee to an
average of $ 62 per year, but vary the fee according to the amount of the vehicle’s
emissions. Vehicles that pollute more would pay higher fees, and those that pollute less
would pay lower fees.
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• Flat mileage fee: Eliminate the eighteen- cents- per- gallon state gas tax altogether and
replace it with a fee based on the number of miles driven. Each driver would pay a fee
of one cent per mile for every mile driven within the state. For example, every one
hundred miles driven would pay a fee of one dollar. Vehicles would be equipped with
an electronic means to keep track of miles driven and the fee would be paid when
drivers buy gas.
• Green mileage fee: Create a variation on the mileage fee previously described, where
the fee varies depending upon how much the vehicle pollutes. On average, vehicles
would pay one cent per mile, but vehicles that pollute the least would pay less and
vehicles that pollute the most would pay more per mile.
One additional question in this section of the survey probed whether or not respondents would
be more likely to support a green transportation fee if they knew the revenues would be
dedicated to programs promoting environmentally friendly transportation. Specifically, the
survey asked if they would be more or less likely to support the vehicle registration fee increase
if the additional money raised “ were dedicated for transportation projects that would help
reduce smog and greenhouse gases— projects like converting transit and school buses to
cleaner fuels, or building new biking and walking paths.”
A second goal of the project was to identify the population subgroups particularly likely to
either support or oppose green transportation taxes and fees. From the phone numbers, the
authors were able to link the respondents to their region within the state. In addition, the
questionnaire asked respondents question about:
• Socio- demographic characteristics, such as age, gender, employment status,
household income, and voter registration status.
• Basic travel behavior patterns, including how many miles per year they drive, and
whether they had walked, biked, or taken transit in the past week.
• Opinions about the importance of key policy issues in California related to the
transportation system and environmental issues.
• Knowledge about transportation finance and the interaction between vehicle use and
the environment.
The full text of the questionnaire is available in Appendix A.
Survey Implementation
A total of 1,500 California adults were interviewed by phone from January 20 to February 1,
2008.48 Interviews were conducted in English and Spanish, and they lasted an average of 13
minutes.
The telephone numbers used were a computer- generated random sample, assuring that both
listed and unlisted phones were included. However, cell phone numbers were not purposely
included. This could result in the underrepresentation of younger adults in the sample, as they
are more likely not to have a land- line phone. Each number was called back up to six times to
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Survey Design and Administration 25
increase the likelihood of completing interviews with eligible households. To counter the
tendency of women and older people to answer the household telephone, a systematic
screening method was used at the household level; surveyors asked to speak to the youngest
male available, and then, if no male were available, to the youngest female in the household
who was at least eighteen years old.
The overall margin of error for the survey is ± 2.5% at the 95% confidence level. Results were
weighted slightly to correspond to 2000 U. S. Census data for gender and region within the
state.
26 Survey Design and Administration
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Mineta Transportation Institute
27
SURVEY RESULTS
SURVEY RESPONDENTS
To assess how well the survey respondents represent the California population, the authors
compared the sample’s demographic characteristics to those for the state’s population, using
data from the 2006 American Community Survey ( ACS) and the U. S. Census population
estimates for California counties ( see Table 3). 49 In general, this study’s sample population is
quite similar to the overall California population, although there are some minor differences.
Therefore the authors are confident that the survey results provide useful insight into the
attitudes and opinions of Californians.
Women represented 55% of the survey’s respondents, compared to 50% of California adults.
In addition, a higher percentage of the survey respondents were older adults than in the full
population; 43% of respondents were over 55 years old, compared to just 27% from the 2006
ACS. Only 38% of the survey sample were between the ages of 25 to 54 years old, compared to
59% in the overall population. These results are not unexpected, as older adults may have
more time to participate in a phone survey than do working- age adults, and they are also less
likely than younger adults to own a cell phone but no land line. Respondents were also more
likely to own their home ( 71% compared to 60% from the 2006 ACS) and have more formal
education. Seventy- nine percent of the survey respondents had more than a high school degree,
compared to only 57% of California adults aged 25 or older. Other demographic categories,
including employment and income, as well as the geographic location of the respondents,
showed very little difference between the study’s sample and the state’s population.
Table 4 presents a summary of information about the survey respondents’ travel behavior and
also some information they reported about the vehicle they drive the most often. Like most
Californians, the respondents relied on their cars for much of their travel. For example, 76%
drive alone to work, and 41% drive over 7,500 miles a year. Respondents were asked to
describe the vehicle that they drive most often, and the majority described their vehicle as a
passenger car ( 62%). Sixty- one percent drive vehicles that are from the 2000 model year or
newer, and 43% drive vehicles with a reported fuel efficiency of 23 miles per gallon or better.
As for use of alternative modes of travel, 14% of respondents said they commute to work
either by transit, carpooling, biking, or walking, 34% said they had walked or biked from
home in the past 7 days for some utilitarian purpose, and only 13% had taken transit in the
past 7 days.
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Table 3 Socio- demographic characteristics of survey respondents and of all Californians
Socio- Demographic Category
Percent of Survey
Respondentsa
a. Percentages may not total to 100% due to rounding.
Percent of Californians ( U. S.
Census Data)
North/ South b
b. Survey data for geographic location and gender are unweighted. Subsequent data analyses weight
these categories to correspond to the state’s population.
North 43 39
South 57 61
Regionb
Bay Area 22 19
Los Angeles 27 27
Other Southern Calif. 24 28
Central Valley 18 17
Central Coast 5 6
Rural CA 4 2
Genderb
Male 45 50
Female 55 50
Age
18- 24 years 19 14
25- 54 years 38 59
55+ years 43 27
Own/ rent residence
Own 71 60 c
c. ACS data is for the entire population, not restricted to adults only.
Rent 29 39
Education level
High school or less 21 43 d
d. ACS data is based on adults 25 years and older.
More than high school 79 57 d
Employed
Yes– full time 50 60 e
e. ACS data does not delineate between full and part- time employment, and data is for persons aged 16
years and older.
Yes– part time 12
No 38 40
Household income
Less than $ 50,000 38 44
$ 50,000–$ 100,000 34 31
Likely Voter?
Yes 73 n. a.
No 27 n. a.
Political affiliation
Democrat 47 n. a.
Republican 33 n. a.
Other 17 n. a.
Don’t know 3 n. a.
Sources: U. S. Bureau of the Census, “ Selected Social Characteristics in California: 2006,” results from
the 2006 American Community Survey, http:// factfinder. census. gov ( accessed March 3, 2009); U. S.
Bureau of the Census, Annual Estimates for the Population for Counties of California: April 1,
2000- July 1, 2007 ( CO- EST2007- 01- 06),
http:// census. gov/ popest/ counties/ tables/ CO- EST2007- 01- 06. xls ( accessed March 3, 2009).
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Survey Results 29
Table 4 Travel behavior information and data about the vehicle respondents drive most
often
Travel Behavior and Vehicle Questions
Percent of
Respondents
“ How do you usually commute to work?” a( Question D8)
a. Asked only of respondents who worked.
Drive yourself 76
Transit, carpool, bike, walk 14
NA– work at home 10
“ In the past seven days, have you taken any form of public transit, like a bus, light
rail, subway, or commuter train?” ( Question 9)
Yes 13
No 87
Don’t know < 1
“ In the past seven days, have you walked or biked from your home to get to work,
shopping, eating out, or other errands?” ( Question 10)
Yes 34
No 66
Don’t know < 1
“ About how many miles did you, personally, drive during the past 12 months in all
motorized vehicles? Please exclude miles you drove as part of a job.” ( Question 11)
1– 3,000 26
3,001– 7,500 21
7,501– 12,500 22
12,501+ 19
NA– don’t drive 6
Don’t know 7
“ What is the model year of this vehicle?” ( Question 13)
2004– 2008 32
2000– 2003 29
1951– 1999 36
Don’t drive 2
Don’t know 2
“ What type of vehicle is it? Is this vehicle a . . .” ( Question 14)
Passenger car 62
Van or minivan 8
Sport utility vehicle 16
Pickup truck/ truck 13
Other 1
“ What is the approximate fuel efficiency of this vehicle? In other words, how many
miles per gallon does the vehicle get?” ( Question 16)
28– 75 MPG 23
23– 27 MPG 20
18– 22 MPG 28
13– 17 MPG 12
< 13 MPG 4
Don’t know 14
Note: The percentages within each category may not sum to 100%, due to rounding.
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SUPPORT FOR THE GREEN TRANSPORTATION TAXES AND FEES
Table 5 presents statewide support levels for the five transportation tax and fee options tested
in the survey. The green options proved popular, with majorities of the respondents
supporting all three green taxes and fees tested. For example, 66% percent of respondents
supported the feebate proposal, and only 30 percent opposed it.
The green taxes were also much more popular than the flat- rate taxes. In the two cases
respondents were asked their support for both a flat- rate and green version of the same tax,
respondents were twenty or more percentage points likely to prefer the green versions. For
example, the survey found that almost two- thirds of respondents ( 63%) supported a green
version of raising the vehicle registration fee, but when respondents were asked if they would
support increasing the vehicle registration fee from $ 31 to a flat rate of $ 62 for everyone, only
41% supported the increase. Comparing the two results shows that converting the fee increase
from a flat- rate one to a green version boosts support by 22 percentage points, or from
less- than- majority support to almost two- thirds support.
Californians once again showed their preference for green transportation tax options when
asked about two versions of a hypothetical mileage fee that would replace the state gas tax of
18 cents. Respondents were told that the gas tax would be replaced with a fee of one cent for
every mile driven within the state. Vehicles would be equipped with an electronic means to
track the miles driven, and the mileage fee would be paid when the driver bought gas. Only
28% of respondents favored this system when the fee was a flat rate for everyone, but support
jumped to 50% when respondents were asked if they would support a green version of the
mileage fee. In this green fee system, the fee rate would vary according to how much the
vehicle pollutes, with less- polluting vehicles paying less per mile and more- polluting vehicles
paying more per mile. The lower levels of support for both of these options may be due, in
part, to respondents’ concerns over privacy, stemming from the need to “ track” vehicle miles
driven.
An additional question in the survey asked respondents if they would be more or less likely to
support the green vehicle registration fee increase if the revenues were dedicated to
transportation programs that would reduce smog and greenhouse gases. Sixty- four percent of
respondents said they would be more likely to support the fee, 20% said they would be less
likely, and 10% said it would make no difference to them.
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Support By Socio- Demographics, Travel Behavior, and Vehicle Choices
A main goal of the research project was to identify subgroups within the state population who
are particularly likely to support or oppose green transportation taxes and fees. This section
presents a series of tables showing the percent of people who said they supported each green
tax or fee measure, or who said they didn’t know, broken down by different groups within the
population. “ Support” was defined as those who said they strongly or somewhat supported the
measure. The report includes tables showing support for the three green transportation tax and
fee policies based on respondents’ socio- demographic characteristics ( Table 6), travel behavior
( Table 7), vehicle ownership ( Table 8), opinions on air pollution, traffic congestion, and
transportation system quality ( Table 10), opinions on the adequacy of transportation revenues
and principles of structuring vehicle registration fees ( Table 12), knowledge of transportation
and environmental issues ( Table 14), and opinions on environmental policy topics ( Table 16).
Each table breaks the survey respondents into sub- groups ( as an example, household income
categories) and shows the percentage of respondents in each sub- group who support each of the
three green policies, as well as the percentage indicating they did not know if they supported
or opposed the policy. The authors used a statistical test, the “ test of two proportions”
explained below, to determine whether there was a statistically significant difference in
support between some of the sub- groups. In all cases, the authors assigned the first sub- group
listed in its section of the table ( for example, households earning less than $ 50,000 annually)
as the “ base” case. This base case was then compared the proportion of respondents in this
sub- group who supported the green policies to the rest of the sub- groups within that category.
Values identified with an * or ** indicate that the difference in support between the “ base”
case and that sub- group is significant at the α≤ 0.05 and α≤ 0.01 levels of significance,
respectively. For some cases, the number of respondents in a sub- group who supported the
policies was too small to run the significance test; these cases are presented with grey text.
The statistical test used in these analyses, the test of two proportions, assesses whether the
differences among sub- groups are statistically significant. This statistical test compares two
proportions ( or percentages) from two different samples to determine whether the difference
Table 5 Statewide support levels for the five transportation tax and fee options
Tax or Fee
Support Oppose Don’t
Strongly Somewhat Overalla Know n
a. Sum of those who said they “ strongly” or “ somewhat” supported the proposal.
Strongly Somewhat Overalla
Vehicle registration fee increase
Flat 18 23 41 39 16 55 5 1494
Green 37 27 63 24 9 33 4 1493
Mileage fee ( to replace state gas tax)
Flat 12 16 28 52 12 65 7 1496
Green 25 25 50 35 11 46 5 1491
Feebate system 38 27 65 20 10 30 4 1489
Note: Some percentages do not sum to 100% due to rounding.
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between the proportions is statistically significant or not. For example, this test allowed the
authors to assess whether the percentage of respondents from Northern California who support
the green vehicle registration fee is statistically different from the percentage of Southern
California respondents who support the same policy. The test statistic, in the form of a z- score,
is calculated as follows:
where π 1 and π 2 are the proportions for each sample, p is the average proportion for the two
samples weighted by sample size, and n1 and n2 represent the individual sample sizes. The null
hypothesis is that there is no statistically significant difference between the two proportions,
and the authors used a two- tailed test with both an α< 0.01 level and an α< 0.05 level of
significance to assess whether the results are statistically significant or not.
The first of this series of tables, Table 6, looks at support levels broken down by region within
the state and basic socio- demographic categories of gender, age, homeowner status, education,
employment status, household income, political party affiliation, as well as whether or not the
respondent is a likely voter. Likely voters were identified as those respondents who are
currently registered to vote, who know which political party they are registered in, and
indicate that they vote occasionally or more often.
One noteworthy finding is that in only a handful of cases did any group have less than
majority support for any of the three green tax and fee proposals. Also, there were surprisingly
few statistically significant differences among the groups, comparing the responses within
each category ( for example, income) to the “ base” case used for the test, as described above. For
example, there was no significant difference in support for any of the three taxes or fees based
on whether respondents were likely voters or not, household income, employment status,
homeowner status, or whether respondents lived in the north or south of California.
However, a few differences did show up. For example, Republicans were from 15 to 19
percentage points less likely to support the three green transportation tax and fee policies than
were Democrats. This result was expected, as prior research suggests that political ideology is
an important indicator of environmental concern. Conservatives are, in general, less likely to
express concern for the environment or to engage in pro- environmental behavior. 50
z =
π 1 − π 2
p( 1− p) 1
n 1
+ 1
n 2
⎛
⎝
⎜
⎞
⎠
⎟
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Survey Results 33
Table 6 Support for the green fee policies, by socio- demographic categories and region
Demographic Category
Green Vehicle
Registration Fee Green Mileage Fee Feebate
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
All respondents 63 4 50 5 66 4
North/ South
North 67 4 50 4 69 4
South 61 4 50 5 64 5
Region
Bay Area 70 4 53 4 72 2
Los Angeles 65 4 51 5 66* 6
Other Southern Calif. 59* 4 50 4 62 4
Central Valley 60* 6 47 6 65 7
Central Coast 61 6 46 1 62 5
Rural CA 64 3 45 3 62 3
Gender
Male 60 3 45 4 64 3
Female 66 5 55** 5 67 5
Age
18– 24 years 70 3 57 3 66 4
25– 54 years 66 4 49 4 68 3
55+ years 61* 4 50 4 65 6
Own/ rent residence
Own 62 4 49 4 66 3
Rent 68 5 53 6 64 7
Education level
High school or less 60 6 52 6 55 9
More than high school 65 4 50 4 69** 3
Employed
Yes– full time 65 3 49 3 68 2
Yes– part time 66 4 50 7 67 3
No 61 6 52 6 64 7
Household income
Less than $ 50,000 64 6 54 5 65 7
$ 50,000– $ 100,000 64 2 52 3 70 2
Over $ 100,000 66 2 46 3 68 3
Likely voter?
Yes 65 3 50 4 67 4
No 59 7 51 6 61 7
Political affiliation
Democrat 73 4 57 4 75 4
Republican 54* 3 42** 4 58** 3
Other 64* 2 44* 3 61** 4
Don’t know 46 19 36 19 68 11
* p ≤ 0.05
** p ≤ 0.01
Notes: The test of two proportions was used to check if there was a statistically significant difference between
“ support” levels among sub- groups. ( No test was run on the “ don’t know” proportions). The first sub- group listed
in each category is the “ base” case for the test; it is compared to the proportion of respondents who supported the
green policies in each of the other sub- groups within that category. For the“ support” levels noted in italic type, too
few respondents supported the policies to run the test of two proportions.
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Breaking down residents into geographic regions revealed that Bay Area respondents were the
most likely to support all three green taxes and fees, although in every region and for every tax
there was at least majority support, with only three exceptions. ( The three exceptions were
support by Central Valley, Central Coast, and rural California residents for the green mileage
fee.) The difference in the percent of supporters between the Bay Area and the other regions
was not especially large, varying from just two percentage points in one case up to 11
percentage points. In only a few cases were the differences statistically significant. The
difference was statistically significant for the registration fee when comparing support levels in
the Bay Area to Southern California outside Los Angeles and to Central Valley residents. Bay
Area respondents were also statistically significantly more likely to support the feebate than
Los Angeles residents. The differences in support by region may reflect political differences
among the regions, as the Bay Area has a considerably higher proportion of Democrats than do
other regions of the state.
Women were moderately more likely to support all three policies, although the difference was
only significant for the mileage fee proposal. Fifty- five percent of women favored this,
compared to 45% of men. This result is also in line with previous findings that indicate
women are more willing to pay more for green products than men and are thus likely to be
more supportive of a green transportation fee. 51
Age played a similarly modest role, somewhat contrary to expectations. A priori, the authors
expected younger respondents to be generally more supportive of the green policy options as
the literature review revealed a tendency for older adults to be less supportive of “ green”
products, but this was true only to a small extent. 52 The oldest group, those 55 years or older,
were indeed the least likely to support two of the proposals, but the difference between the
oldest and youngest group was only significant for the green registration fee proposal ( 70%
support for the youngest group and 61% for the oldest group). There were no real differences
in level of support by age for the feebate proposal.
As for education, only one significant difference was revealed between those who had attended
college compared to those who had not: those who had formal schooling beyond high school
were 14 percentage points more likely to support the feebate proposal. The weak link between
education and support for the green taxes was surprising, since prior research looking at the
characteristics of “ green” consumers finds education to be a strong and consistent indicator of
pro- environmental behavior. 53
As with socio- demographic factors, there were surprisingly few significant differences in
support levels when respondents were sorted into groups based on key travel behavior factors
such as their usual commute mode, how many miles they drove in the last twelve months,
whether they have cut back their driving in response to higher fuel prices, and whether or not
they have taken transit or biked or walked in the past seven days ( see Table 7). Also, support
levels were at 50% or above for almost every sub- group and every tax and fee proposal.
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Survey Results 35
However, there were a few significant differences based on whether respondents had used
transit or walked or biked, and how much they had cut back on driving in response to the
recent rise in fuel prices. Thirteen percentage points fewer of the respondents who had not
taken transit in the past seven days supported the green registration fee increase ( 62% versus
75%), though there was no significant difference in their support levels for the other two
Table 7 Support for the green fee policies, by travel behavior
Travel Behavior Categories
Green Registration Fee
Increase Green Mileage Fee Feebate
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
All respondents 63 4 50 5 66 4
“ How do you usually commute to work?” ( Question D8)
Drive yourself 64 3 48 3 67 2
Use transit, carpool,
bicycle or walk 73 5 55 7 69 5
NA– work at home 63 0 50 3 70 1
“ In the past seven days, have you taken any form of public transit, like a bus, light rail, subway, or commuter
train?” ( Question 9)
Yes 75 4 55 8 71 6
No 62** 4 50 4 65 4
Don’t know 33 0 0 33 33 0
“ In the past seven days, have you walked or biked from your home to get to work, shopping, eating out, or
other errands?” ( Question 10)
Yes 69 5 54 6 70 6
No 60** 4 48 4 63* 4
Don’t know 100 0 100 0 100 0
“ About how many miles did you, personally, drive during the past 12 months in all motorized vehicles? Please
exclude miles you drove as part of a job.” ( Question 11)
1– 3,000 66 4 52 5 66 4
3,001– 7,500 63 3 49 3 64 4
7,501– 12,500 65 3 48 3 68 2
12,501+ 60 3 46 3 68 3
NA– don’t drive 61 13 59 10 53 18
Don’t know 63 6 53 9 63 8
“ As a result of the recent rise in gasoline prices, how much, if any, have you cut back on your driving? Have
you cut back a lot, a little or not at all?” ( Question 12)
Cut back a lot 62 5 55 2 66 5
Cut back a little 69 4 51 6 71 3
Not at all 59 3 44* 3 63 3
NA– don’t drive 75 4 50 16 67 4
Don’t know 100 0 67 33 100 0
* p ≤ 0.05
** p ≤ 0.01
Notes: The test of two proportions was used to check if there was a statistically significant difference between
“ support” levels among sub- groups. ( No test was run on the “ don’t know” proportions). The first sub- group
listed in each category is the “ base” case for the test; it is compared to the proportion of respondents who
supported the green policies in each of the other sub- groups within that category. For the “ support” levels
noted in italic type, too few respondents supported the policies to run the test of two proportions.
36 Survey Results
Mineta Transportation Institute
green fees. Also, the group of respondents who had not walked or biked from home to get
somewhere in the past seven days were nine percentage points less likely to support the vehicle
registration fee increase and seven percentage points less likely to support the feebate system,
though their support for the mileage fee was not significantly different. Finally, only 44% of
respondents who said that they had not cut back their driving in response to higher gasoline
prices were likely to support the green mileage fee, 11 percentage points less than the group
who had cut back their driving a lot.
The survey asked respondents some questions about the vehicle they “ drive the most.” More
striking differences among subgroups showed up here than in the preceding tables. As shown
in Table 8, vehicle model year had no significant impact on whether respondents said they
would support any of the three green fee policies. However, vehicle type had some impact.
Respondents who said they drove pickup trucks or trucks were less likely than drivers of
passenger cars to support both the green vehicle registration fee and the feebate system. The
percentage of drivers of vans and SUVs who supported the green taxes and feed varied, ranging
from two percentage points more supportive than passenger car drivers to 10 percentage
points less supportive than passenger car drivers, although none of these differences were
statistically significant.
Vehicle fuel efficiency also had an impact on support levels. In general, support levels drop as
fuel efficiency gets lower, varying by as much as 17 percentage points compared to the other
sub- groups for which there were enough respondents to run the significance test. The
respondents with the least fuel efficient vehicles were even less likely to support the green fee
policies, though there were too few of them to test if the difference is statistically significant.
Finally, drivers who said that gas mileage was a “ not very” or “ not at all important” factor
when they purchased or leased the vehicle were less likely to support all three policies than
those drivers who said gas mileage was a somewhat or very important factor. Here the
differences ranged from 11 to 19 percentage points ( and were statistically significant).
Support By Opinions and Knowledge About Policy Issues in California
The survey also looked at the extent to which respondents’ views on the green transportation
tax and fee policies might vary according to their opinions and knowledge about policy issues
in California, especially policies related to transportation and environmental issues. Previous
research related to both transportation and environmental behavior indicates that people’s
attitudes toward the environment may correlate with their support for green policies. In
addition, attitudes for one green behavior or product may carry over to views on other green
products and behaviors. 54 Finally, knowledge can also be a key factor that influences people’s
opinions and behavior. 55 To test whether these expected relationships might hold with respect
to support for green taxes and fees, the survey included questions to assess respondents’
knowledge about how much motor vehicles contribute to global warming and air pollution, as
well as some basic facts about transportation finance in California.
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Survey Results 37
Table 9 shows how respondents answered a series of four questions asking how much of a
problem they perceived air pollution, traffic congestion, and the “ quality of the transportation
system” to be. Virtually all respondents answered that pollution and traffic congestion are a
big problem or somewhat of a problem for the state as a whole, but only about half said that
the transportation system or air pollution are problems for them personally or for their
Table 8 Support for green fee policies, by type of vehicle respondent drives the most
Vehicle Type Categoriesa
a. These questions were introduced with the line, “ Now I have a few questions about the vehicle you drive
the most.”
Green Registration Fee
Increase Green Mileage Fees Feebate
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
All respondents 63 4 50 5 66 4
“ What is the model year of this vehicle?” ( Question 13)
2004– 2008 64 2 51 3 70 2
2000– 2003 61 5 47 5 67 4
1951– 1999 66 5 49 4 65 4
Don’t drive 61 4 52 9 44 4
Don’t know 52 4 54 11 52 11
“ What type of vehicle is it? Is this vehicle a . . .” ( Question 14) ALTERNATE CATEGORIES
Passenger car 67 4 53 4 70 3
Van or minivan 67 5 55 7 68 5
Sport utility vehicle 64 1 43 3 64 3
Pickup truck/ truck 48** 3 39 4 57** 5
Other 27 0 9 9 46 9
“ What is the approximate fuel efficiency of this vehicle? In other words, how many miles per gallon does
the vehicle get?” ( Question 16)
28– 75 MPG 75 3 55 4 75 3
23– 27 MPG 63** 4 43* 6 67 2
18– 22 MPG 63** 2 48 3 66* 2
13– 17 MPG 49** 5 38* 2 63* 4
< 13 MPG 46 6 33 2 40 6
Don’t know 67 6 64 4 67 8
“ When you purchased or leased this vehicle, how much of a factor was gas mileage? Was it a very
important factor, somewhat important, not very important, or not important at all?” ( Question 17)
Very/ somewhat
important 70 3 53 3 71 3
Not very important/ not
important at all 51** 4 42** 4 58** 4
Don’t know 64 13 39 23 59 5
* p ≤ 0.05
** p ≤ 0.01
Notes: The test of two proportions was used to check if there was a statistically significant difference
between “ support” levels among sub- groups. ( No test was run on the “ don’t know” proportions). The
first sub- group listed in each category is the “ base” case for the test; it is compared to the proportion of
respondents who supported the green policies in each of the other sub- groups within that category. For the
“ support” levels noted in italic type, too few respondents supported the policies to run the test of two
proportions.
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Mineta Transportation Institute
families. This finding suggests people have a broad awareness of and concern with
transportation and transportation- related issues, even if they do not feel personally impacted
by certain problems.
As shown in Table 10, support for the three policies varied significantly by how respondents
answered three of the four questions asking respondents about how much of a “ problem” they
perceived the transportation and air quality issues to be. The questionnaire was structured to
ask pairs of questions about whether respondents saw transportation and air quality issues as
problems for them and their families, and also as problems “ in California.” In both cases,
support for the green policies varied more markedly among the subgroups on the questions
about statewide significance than for the questions about personal significance.
First, there was no statistically significant difference in support levels for the fees based on
whether or not respondents perceived the quality of the transportation system to be a problem
for them or their families, but responses did vary according to how much of problem
respondents saw traffic congestion to be in the state. A higher percentage of those who saw
traffic congestion as a problem in California supported two of the three policies, with large
differences of twenty percentage points or more.
Table 9 Respondents’ opinion on air pollution, traffic congestion, and transportation
system quality
Question
Big or
Somewhat of a
Problem
(%)
Not Much of or
No Problem
(%)
Don’t Know
(%) n
“ Do you think that smog and air pollution is a big
problem, somewhat of a problem, not much of a
problem, or not problem at all in California?”
90 10 < 1 1499
“ What about traffic congestion? Do you think
that traffic congestion is a big problem,
somewhat of a problem, not much of a problem,
or no problem at all in California?”
94 6 1 1500
“ Now I’d like to know if the quality of the
transportation system is a problem for you or
your family? By the transportation system, I
mean highways, local streets, and transit. Is it a
big problem, somewhat of a problem, not much
of a problem, or no problem at all?”
56 43 1 1499
“ Now I’d like to know if air pollution is a health
problem for you or your family. Would you say it
is a big problem, somewhat of a problem, not
much of a problem, or no problem at all?”
48 51 1 1500
Note: Some percentages do not sum to 100% due to rounding.
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Survey Results 39
Following the same pattern, there were modest differences in support for all three policy
options by how much of a problem respondents saw air pollution to be for them or their
families ( from 8 to 13 percentage point differences), but much bigger differences in support
exist between the sub- groups who did and didn’t see smog and air pollution to be a problem in
California. Here, the differences ranged from 15 to 23 percentage points between the
sub- groups.
Another section of the survey asked respondents their opinions on several questions related to
transportation finance in California. Table 11 presents the responses to those questions. A
minority of respondents though that state and local government have sufficient revenues to
maintain and improve the transportation system ( 32%). When asked whether vehicle
registration fees should, on principle, vary according to vehicle gas mileage or pollution
Table 10 Support for the green fee policies, by opinions on air pollution, traffic
congestion, and transportation system quality
Opinions
Green Registration Fee
Increase Green Mileage Fee Feebate
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
All respondents 63 4 50 5 66 4
“ Do you think that smog and air pollution is a big problem, somewhat of a problem, not much of a problem,
or not problem at all in California?” ( Question 1)
Big/ somewhat problem 65 4 51 4 68 4
Not much/ no problem 48** 5 36* 5 45** 7
Don’t know 86 14 86 14 57 29
“ What about traffic congestion? Do you think that traffic congestion is a big problem, somewhat of a
problem, not much of a problem, or no problem at all in California?” ( Question 2)
Big/ somewhat problem 65 4 51 4 67 4
Not much/ no problem 43** 9 40 5 47** 9
Don’t know 56 0 33 33 56 22
“ Now I’d like to know if the quality of the transportation system is a problem for you or your family? By the
transportation system, I mean highways, local streets, and transit. Is it a big problem, somewhat of a
problem, not much of a problem, or no problem at all?” ( Question 3)
Big/ somewhat problem 66 3 49 5 68 3
Not much/ no problem 60 6 51 4 63 7
Don’t know 56 13 44 6 63 0
“ Now I’d like to know if air pollution is a health problem for you or your family. Would you say it is a big
problem, somewhat of a problem, not much of a problem, or no problem at all?” ( Question 4)
Big/ somewhat problem 69 5 57 4 70 5
Not much/ no problem 58** 4 44** 5 62** 4
Don’t know 50 0 33 33 63 0
* p ≤ 0.05
** p ≤ 0.01
Notes: The test of two proportions was used to check if there was a statistically significant difference between
“ support” levels among sub- groups. ( No test was run on the “ don’t know” proportions). The first sub- group
listed in each category is the “ base” case for the test; it is compared to the proportion of respondents who
supported the green policies in each of the other sub- groups within that category. For the “ support” levels
noted in italic type, too few respondents supported the policies to run the test of two proportions.
40 Survey Results
Mineta Transportation Institute
emissions, 57% agreed with the principle of linking the fees to gas mileage, while 68% agreed
with the principle of linking the fees to emissions rates.
Table 12 shows the correlation between responses to these questions on transportation finance
and support for the three green fee options. Respondents who thought the government had
adequate funds were less likely to support all three green transportation fee policies than those
who thought government did not have adequate funds. The differences fell within a modest
range, from 11 to 14 percentage points. Majorities of the respondents who thought
government already had sufficient revenues nevertheless still supported the green vehicle
registration fee and feebate policies. As for the questions about linking vehicle registration
fees to fuel efficiency and emissions, these revealed unsurprisingly stark differences in support
for the green transportation fee policies tested later in the survey, with the percentage point
differences in support between those who did and did not agree with the two statements
ranging from 35 to 53 percentage points.
The survey also tested respondents’ knowledge of how transportation funds are raised in
California, plus their understanding of the relationship between motor vehicle use and air
pollution and global warming. Table 13 shows that majorities of respondents ( 55% to 74%)
knew the correct answer to all but one question. The one question which the majority of
respondents answered incorrectly related to the gas tax; only 20% of respondents knew that
state and federal gas tax rates have not been raised in more than 10 years. Across all these
questions, fairly high percentages of respondents answered “ don’t know”— from 6% to a high
of 31%.
Table 11 Respondents’ opinions on transportation revenues and principles of structuring
vehicle registration fees
Question
Does
Have/ Yes
(%)
Does Not
Have/ No
(%)
Don’t Know
(%) n
“ Overall, do you think that state and local
government does or does not have adequate
funding to maintain and improve the
transportation system?”
32 49 19 1494
“ Generally speaking, should the fees that people
pay to register their vehicles take into account the
gasoline mileage those vehicles achieve? That is,
should the fees be lower for vehicles that get
more miles per gallon, and higher for vehicles
that get fewer miles per gallon?”
57 34 9 1494
“ As a general principle, should the fees that
people pay to register their vehicles take into
account the amount of pollution those vehicles
emit? That is, should the fees be lower for
vehicles that emit less air pollution, and higher for
vehicles that emit more air pollution?”
68 27 6 1490
Note: Some percentages do not sum to 100% due to rounding.
Mineta Transportation Institute
Survey Results 41
Table 12 Support for the green fee policies, by opinions on transportation revenues and
principles of structuring vehicle registration fees
Opinions
Green Registration Fee
Increase Green Mileage Fee Feebate
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
Support
(%)
Don’t Know
(%)
All respondents 63 4 50 5 66 4
“ Overall, do you think that state and local government does or does not have adequate funding to maintain
and improve the transportation system?” ( Question 5)
Does have 55 3 43 3 58 3
Does not have 69** 3 54** 4 71** 3
Don’t know 64* 8 51 10 63 11
“ Generally speaking, should the fees that people pay to register their vehicles take into account the gasoline
mileage those vehicles achieve? That is, should the fees be lower for vehicles that get more miles per gallon,
and higher for vehicles that get fewer miles per gallon?” ( Question 6)
Yes 80 3 65 4 79 4
No 37** 3 27** 3 45** 3
Don’t know 54** 13 47** 13 57** 15
“ As a general principle, should the fees that people pay to register their vehicles take into account the amount
of pollution those vehicles emit? That is, should the fees be lower for vehicles that emit less air pollution, and
higher for vehicles that emit more air pollution?” ( Question 7)
Yes 80 3 63 4 76 4
No 27** 4 21** 3 41** 4
Don’t know 40** 16 36** 16 56** 11
* p ≤ 0.05
** p ≤ 0.01
Notes: The test of two proportions was used to check if there was a statistically significant difference between
“ support” levels among sub- groups. ( No test was run on the “ don’t know” proportions). The first sub- group
listed in each category is the “ base” case for the test; it is compared to the proportion of respondents who
supported the green policies in each of the other sub- groups within that category.
42 Survey Results
Mineta Transportation Institute
Table 14 presents support for the three green policies according to respondents’ understanding
of the issues. Support levels varied strongly by two issues: whether or not respondents thought
motor vehicle exhaust is an important source of the pollution that causes asthma and whether
or not they thought motor vehicles are the single largest source of greenhouse gases. For these