United States	Air and Radiation	EPA420-S-03-004
Environmental Protection	April 2003
Agency
<&EPA Light-Duty Automotive
Technology and Fuel
Economy Trends:
1975 Through 2003
Executive Summary
Printed on Recycled Paper

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EPA420-S-03-004
April 2003
Light-Duty Automotive Technology and
Fuel Economy Trends:
1975 Through 2003
Executive Summary
Karl H. Hellman
Robert M. Heavenrich
Advanced Technology Division
Office of Transportation and Air Quality
U.S. Environmental Protection Agency
NOTICE
This technical report does not necessarily represent final EPA decisions or positions.
It is intended to present technical analysis of issues using data that are currently available.
The purpose in the release of such reports is to facilitate the exchange of
technical information and to inform the public of technical developments which
may form the basis for a final EPA decision, position, or regulatory action.

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Introduction
This report summarizes key fuel economy and technology usage trends related to model
year 1975 through 2003 light vehicles sold in the United States. Light vehicles are those vehicles
that EPA classifies as cars or light-duty trucks (sport utility vehicles, vans, and pickup trucks with
less than 8,500 pounds gross vehicle weight ratings).
Model year 2003 light vehicles average 20.8 miles per gallon (mpg). New vehicle fuel
economy peaked in 1987 and 1988 at 22.1 mpg and has been on a general downward trend since
1988. The average fuel economy for all model year 2003 light vehicles is six percent lower than it
was in 1988. These fuel economy values are based on 'real world' estimates provided by the
Federal government to consumers and are about 15 percent lower than the fuel economy values
used by manufacturers and DOT for compliance with the Corporate Average Fuel Economy
(CAFE) program.
In order to estimate the average fleet fuel economy for each model year, the measured fuel
economy for each model is weighted by its sales volume. For model year 2003, EPA has used
projected sales data that the auto companies are required to submit to the Agency. When EPA
publishes the 2004 Trends Report, it will provide revised data based on actual sales information
available at that time.
EPA has analyzed the variation in average fleet fuel economy that would have occurred in
previous years as a result of using projected rather than actual sales. The variation is very low—
plus or minus two percent (about 0.5 mpg). Readers therefore are encouraged to keep in mind
that the data presented in this report may change slightly when the figures are re-calculated after
the end of the model year.
Importance of Fuel Economy
Fuel economy continues to be a major area of public and policy interest for several
reasons, including:
1.	Light vehicles account for approximately 40 percent of all U.S. oil consumption. Crude
oil, from which nearly all light-vehicle fuels are made, is considered to be a finite natural
resource.
2.	Fuel economy is directly related to the cost of fueling a vehicle and is of great interest
when oil and gasoline prices rise.
3.	Fuel economy affects the level of the nation's energy efficiency. Increases in energy
efficiency can enhance energy security and reduce emissions of greenhouse gases. Fuel
economy is directly related to carbon dioxide emissions, the most prevalent greenhouse
gas. Light vehicles contribute about 20 percent of all U.S. carbon dioxide emissions.
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Highlight #1: Fuel Economy is 20.8 mpg for Model Year 2003
There has been a general overall declining trend in new light-vehicle fuel economy since
1988. The average fuel economy for all model year 2003 light vehicles is 20.8 mpg - six
percent lower than the peak value of 22.1 mpg achieved in 1987 and 1988. Average
model year 2003fuel economy is 24.8 mpg for cars and 17.7 mpg for light trucks.
New light-vehicle fuel economy improved fleet-wide from the middle 1970s through the
late 1980s, but it has been generally falling since then due primarily to the increase in the sales
fraction of less efficient light-duty trucks. Viewed separately, the average fuel economy for new
cars has changed very little since 1986, varying between 23.6 to 24.8 mpg. Similarly, the average
fuel economy for new light trucks has been largely unchanged since 1986, ranging from 17.3 to
18.4 mpg.
Fuel Economy by Model Year
30
Average MPG
25
Trucks
20
15
10 | l l l l | l l l l | l l l l | l l l l | l l l l | l l l l | l l l l—
1970 1975 1980 1985 1990 1995 2000 2005
Model Year
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Highlight #2: Trucks Represent Nearly Half of New Vehicle Sales
Sales of light trucks, which include sport utility vehicles (SUVs), vans, and pickup trucks,
have risen steadily for over 20 years and now make up 48 percent of the U.S. light
vehicle market—more than twice their market share in 1983.
Growth in the light truck market has been led recently by the increase in the market share
of SUVs. The SUV market share increased by more than a factor of ten, from less than two
percent of the overall new light vehicle market in 1975 to 24 percent of the market in 2003. Over
the same period, the market share for vans increased by 80 percent, while that for pickups
remained relatively constant. Between 1975 and 2003, market share for new passenger cars and
station wagons decreased from 81 to 52 percent. For model year 2003, cars average 24.8 mpg,
vans 19.6 mpg, SUVs 17.8 mpg, and pickups 16.8 mpg.
The increasing market share of light trucks, which in recent years has averaged more than
six mpg less than cars, accounts for much of the decline in fuel economy of the overall new light
vehicle fleet.
Sales Fraction by Vehicle Type
Sales Fraction
Pickup
Model Year
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Highlight #3: Over the Past Two Decades, Fuel Economy Has Been Relatively
Constant, While Vehicle Weight and Power Have Been Increasing
Technologies continue to enter the new light vehicle fleet and are being used, for
example, to increase light vehicle acceleration performance, while fuel economy is not
being increased. Based on accepted engineering relationships, however, had the new
2003 light vehicle fleet had the same average performance and same distribution of
weight as in 1981, it could have achieved about 33 percent higher fuel economy.
Technologies—such as engines with more valves and more sophisticated fuel injection
systems, and transmissions with lockup torque convertors and extra gears—continue to penetrate
the new light vehicle fleet. The trend has clearly been to apply these new technologies to
accommodate increases in average new vehicle weight, power, and performance while maintaining
a constant level of fuel economy. This is reflected by heavier average vehicle weight, rising
average horsepower, and faster average 0 to 60 mile-per-hour acceleration time.
Percent Change from 1981 to 2003
in Average Vehicle Characteristics
100%
75%
50%
25%
0%
Fuel Economy Weight (lbs.) Horsepower 0 to 60 Time (sec)
1% Higher	24% Heavier 93% Higher 29% Faster
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Important Notes With Respect to the Data Used in This Report
Unless otherwise indicated, the fuel economy values in this report are based on laboratory
data and have been adjusted downward by about 15 percent so that this data is equivalent to the
real world estimates provided to consumers on new vehicle labels, in the EPA/DOE Fuel
Economy Guide, and in EPA's Green Vehicle Guide. These adjusted fuel economy values are
significantly lower than those used by the U.S. Department of Transportation (DOT) for
compliance with Corporate Average Fuel Economy (CAFE) standards as, in addition to the 15-
percent downward adjustment for real world driving, they also exclude credits for alternative fuel
capability and test procedure changes that are included in the CAFE data reported by the U.S.
DOT.
When comparing data in this report with those in previous reports in this series, please
note that revisions are made in the data for some recent model years for which more complete and
accurate sales and fuel economy data have become available.
Sales data for recent model years are based on confidential information provided to the
government by the manufacturers. The sales data for model years 2002 and 2003 used in this
report have been adjusted to take into account data available at the time the data base was frozen
in September 2002.
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For More Information
Light-Duty Automotive Technology and Fuel Economy Trends: 1975 through 2003 (EPA420-R-
03-006) is available electronically on the Office of Transportation and Air Quality's (OTAQ) Web
site at:
www.epa.gov/otaq/fetrends.htm
You can also contact the OTAQ library for document information at:
U.S. Environmental Protection Agency
Office of Transportation and Air Quality Library
2000 Traverwood Drive
Ann Arbor, MI 48105
(734)214-4311
The U.S. Department of Energy (DOE) and the U.S. Environmental Protection Agency (EPA)
have a fuel economy Web site that provides city and highway fuel economy data for individual
models. You can also print the guide from the Web site:
www, fueleconomv. gov
A printed copy of the Fuel Economy Guide is available by calling DOE's National Alternative
Fuels Hotline at (800) 423-1363.
EPA's Green Vehicle Guide Web site provides information about the air pollution emissions and
fuel economy performance of vehicles:
www, epa. gov/ greenvehicles/
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