Light-Duty Automotive Technology,
           Carbon Dioxide Emissions, and Fuel
           Economy Trends:
           1975 Through 2011

           Executive Summary
&EPA
United States
Environmental Protection
Agency

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                 Light-Duty Automotive Technology,
                 Carbon Dioxide Emissions, and Fuel
                              Economy Trends:
                            1975 Through 2011

                             Executive Summary
                              Transportation and Climate 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.
&EPA
United States
Environmental Protection
Agency
EPA-420-S-12-001
March 2012

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I.  Executive Summary

Introduction

       This report summarizes key trends in carbon dioxide (CO2) emissions, fuel economy, and CO2- and fuel
economy-related technology for gasoline- and diesel-fueled personal vehicles sold in the United States, from model
years (MY) 1975 through 2011. Personal vehicles are those vehicles that EPA classifies as cars, light-duty trucks
(sport utility vehicles, minivans, vans, and pickup trucks with gross vehicle weight ratings up to 8500 pounds), or,
beginning in MY 2011, medium-duty passenger vehicles (sport utility vehicles or passenger vans with gross vehicle
weight ratings between 8500 and 10,000 pounds). The data in this report cover the MY 1975-2011 timeframe,
supersede the data in previous reports in this series, and should not be compared with data from previous years'
editions of this report due to changes discussed below. Except when noted, CO2 emissions and fuel economy values
in this report have been adjusted to reflect "real world" consumer performance and therefore are not comparable to
CO2 emissions and fuel economy standards.

       Data for MY 2010 are final, but data for MY 2011 are preliminary. The fleetwide average real world MY
2010 personal vehicle CO2 emissions value is 394 grams per mile (g/mi) and fuel  economy is 22.6 miles per gallon
(mpg), both slight improvements over MY 2009 and the most favorable levels since this analysis began in 1975.
Preliminary projections for MY 2011 are for continued slight improvements for both CO2 emissions and fuel
economy. For more discussion  of the key conclusions of this report, see the five Highlights at the end of this
Executive Summary.

What's New This Year

       Most small, 2 wheel drive SUVs have been reclassified from trucks to cars for the entire MY 1975-2011
database. This reflects a regulatory change made by the Department of Transportation's (DOT) National Highway
Traffic Safety Administration (NHTSA) for Corporate Average Fuel Economy (CAFE) standards beginning in MY
2011 and which will apply for the joint EPA/NHTSA greenhouse gas emissions and CAFE standards that have been
finalized  for MY 2012-2016 and proposed for MY 2017-2025. Some examples of the impacts of this change are that,
for MY 2010, nearly 1.1 million vehicles are classified as  cars that in previous years would have been classified  as
trucks, the absolute truck share is nearly 10% lower, the projected average adjusted CO2 emissions for cars are about
9 g/mi higher, the projected average adjusted CO2 emissions for light trucks are 17 g/mi higher, and the projected
average adjusted fuel economies for cars and for light trucks are both 0.7 mpg lower than they would have been under
the previous classification approach.  Since this classification change does not affect the overall number of vehicles,
or vehicle emissions/fuel economy  performance, it has no impact on the  average adjusted CO2 emissions and fuel
economy for the overall (car plus light truck) fleet. When the car fleet is further subdivided into sub-classes, these re-
classified vehicles are referred to as "non-truck SUVs," while the remaining SUVs are termed "truck SUVs."

       Beginning with MY 2011, the database now includes medium-duty passenger vehicles (MDPVs), which
include larger sport utility vehicles  (SUVs) and passenger vans, but not the larger pickup trucks, in the 8500-10,000
pound gross vehicle weight rating (GVWR) range. This change was made because NHTSA includes MDPVs  in its
CAFE standards beginning with MY 2011, and EPA and NHTSA include MDPVs in future greenhouse gas
emissions and CAFE standards  (and vehicle labels as well). While EPA will be including MDPV data for all years
beginning with MY 2011, EPA  does not have data for MDPVs for MY 1975-2010, so there is and will continue to be
a very small discontinuity in the database beginning in MY 2011. The inclusion of MDPVs in MY 2011 increases
projected average adjusted CO2  emissions for light trucks  by about 0.5 g/mi (even less for the overall fleet


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decreases projected average adjusted fuel economy for light trucks by 0.02 mpg (less for the overall fleet) compared
to the fleet without MDPVs.

Important Explanation of Data Contained in This Report

       Final MY 2010 data are based on formal end-of-year CAFE reports submitted by automakers to EPA and will
not change.  The preliminary MY 2011 data in this report are based on confidential pre-model year production
volume projections provided to EPA by automakers during MY 2010 for the fuel economy label program.
Accordingly, there is uncertainty in the MY 2011 data used in this report. For example, while the final MY 2010
values for CO2 emissions and  fuel economy in this report are essentially the same as the projected MY 2010 values
that were provided in last year's report, in some previous years the preliminary projections were not good predictors
of actual CO2 and fuel economy performance. This report will often focus on the final MY 2010  data, rather than on
the preliminary MY 2011 data, as we have done in prior reports.

       The reader is advised to be cautious in making data comparisons between MY 2009 and MY 2010 as the
former was a year of considerable turmoil in the automotive market. Due primarily to the economic recession, light-
duty vehicle production was 34% lower in MY 2009 than in MY 2008, and the lowest since the database began in
1975.

       The great majority of the CO2 emissions and fuel economy  values in this report are adjusted (ADJ) EPA real-
world estimates provided to consumers and based on EPA's 5-cycle test methodology (which represent city, highway,
high speed/high acceleration, high temperature/air conditioning, and cold temperature driving) that was first
implemented in MY 2008. Appendix A provides a detailed explanation of the method used to calculate these
adjusted fuel economy and CO2 values, which last changed with the 2007 version of this report.  In 2011, EPA and
NHTSA revised the fuel economy and environment label to include, among other things, CO2 emissions per mile and
a fuel economy and greenhouse gas emissions rating (76 Federal Register 39478, July 6, 2011).

       In some tables, the report also provides unadjusted EPA laboratory (LAB) values, which are based on a 2-
cycle test methodology (city and highway tests only) and are the basis for automaker compliance with CO2 emissions
and CAFE standards.  All combinations of adjusted or laboratory, and CO2 emissions or fuel economy values, may be
reported as  city, highway, or, most commonly, as composite (combined city/highway, or COMP).

       Because the underlying methodology for generating unadjusted laboratory CO2 emissions and fuel economy
values has not changed since this series began in the mid-1970s, these values provide a basis for comparing long-term
CO2 emissions and fuel economy trends from the perspective of vehicle design, apart from the factors that affect real-
world driving that are reflected in the adjusted values.  These unadjusted laboratory values form the basis for
automaker compliance with CO2 emissions and CAFE standards. Laboratory composite values represent a harmonic
average of 55 percent city and 45 percent highway operation, or "55/45." For 2005 and later model years, unadjusted
laboratory composite CO2 emissions values are, on average, about 20 percent lower than adjusted composite CO2
values, and unadjusted laboratory composite fuel economy values are, on average, about 25 percent greater than
adjusted composite fuel economy values.

Regulatory Context

        CAFE standards have been in place since 1978. NHTSA has the responsibility for setting and enforcing
CAFE standards.  EPA is responsible for establishing fuel economy test procedures and calculation methods, and for
collecting data used to determine vehicle fuel economy and manufacturer CAFE levels. For MY 2011, the footprint-
based CAFE standards are projected to achieve average industry-wide compliance levels of 30.4 mpg for cars

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(including a 27.8 mpg alternative minimum standard for domestic cars for all manufacturers) and 24.4 mpg for light
trucks (75 FR25330, May 7, 2010).  There are no greenhouse gas emissions standards for MY 2011.

       For MY 2012 and later, EPA and NHTSA have been jointly developing a harmonized National Program to
establish EPA greenhouse gas emissions standards and NHTSA CAFE standards that allow manufacturers to build a
single national fleet to meet requirements of both programs while ensuring that consumers have a full range of
vehicle choices. The National Program has been supported by a wide range of stakeholders: most major automakers,
the United Auto Workers, the State of California, and major consumer and environmental groups.

       In 2010, the agencies finalized the first harmonized standards for MY 2012-2016 (75 Federal Register 25324,
May 7, 2010). The standards for MY 2012 are now in effect.  By MY 2016, the average industry-wide compliance
levels for these footprint-based standards are projected to be 250 g/mi CO2 and 34.1 mpg CAFE.  The 250 g/mi CO2
compliance level would be equivalent to 35.5 mpg if all CO2 emissions reductions are achieved through fuel economy
improvements. In 2011, the agencies proposed additional harmonized standards for MY 2017-2025 (76 FR 74854,
December 1, 2011). Under the currently-proposed footprint-based standards, by MY 2025 the average industry-wide
compliance levels are projected to be 163 g/mi CO2 and 49.6 mpg CAFE. The 163 g/mi CO2 compliance level would
be equivalent to 54.5 mpg if all CO2  emissions reductions are achieved solely through improvements in fuel
economy. For both MY 2012-2016 and MY 2017-2025, the agencies expect that a portion of the required CO2
emissions improvements will be achieved by reductions in air conditioner refrigerant leakage, which would not
contribute to higher fuel economy.

       These projected levels for MY 2025 represent an approximate halving of CO2 emissions and doubling of fuel
economy levels since the National Program was announced in May 2009. Taken together, the MY 2011 CAFE
standards, the MY 2012-2016 greenhouse gas emissions and CAFE standards, and the proposed MY 2017-2025
greenhouse gas emissions and CAFE standards are projected to save approximately 6 billion metric tons of
greenhouse gas emissions and 12 billion barrels of oil over the lifetimes  of the vehicles produced in MY 2011-2025.
Based on the agencies' most recent estimates of the cost and effectiveness of future technologies,  Department  of
Energy forecasts of future fuel prices, and other assumptions, the fuel savings to consumers are projected to far
outweigh the higher initial cost of the vehicle technology that will be necessary to meet the new standards.

       With real world (i.e., 5-cycle label) adjustments, alternative fuel vehicle credits, and test procedure
adjustments, fleetwide CAFE compliance values are a minimum of 25 percent higher than EPA adjusted (5-cycle)
fuel economy values. See Appendix A for a detailed comparison of EPA adjusted and laboratory fuel economy
values and CAFE compliance values.
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Highlight #1: MY 2010 had the lowest COi emission rate and highest fuel economy since the database
              began in 1975.
        MY 2010 adjusted composite CO2 emissions were 394 g/mi, a record low for the post-1975
        database and a 3 g/mi decrease relative to MY 2009. MY 2010 adjusted composite fuel economy
        was 22.6 mpg, an all-time high since the database began in 1975, and 0.2 mpg higher than in MY
        2009. Preliminary MY 2011 values are 391 g/mi CO2 emissions and 22.8 mpg fuel economy,
        reflecting slight improvements over MY 2010.
       While year-to-year changes often receive the most public attention, the greatest value of the historical trends
database is the identification and documentation of long-term trends. Since 1975, overall new light-duty vehicle CO2
emissions have moved through four phases: 1) a rapid decrease from MY 1975 through MY 1981; 2) a slower
decrease until reaching a valley in MY 1987; 3) a gradual increase until MY 2004; and 4) a decrease for the seven
years beginning in MY 2005, with the largest decrease in MY 2009.  Since fuel economy has an inverse relationship
to tailpipe CO2 emissions, overall new light-duty vehicle fuel economy has moved in opposite phases.

       The recent improvements in CO2 emissions and fuel economy reverse the trend of increasing CO2 emissions
and decreasing fuel economy that occurred from MY 1987 through MY 2004. From MY 2004 to MY 2010, CO2
emissions decreased by 67 g/mi (15 percent), and fuel economy increased by 3.3 mpg (17 percent).  Priorto MY
2009, the previous records for lowest CO2 emissions and highest fuel economy were in MY 1987. Compared to MY
1987, MY 2010 CO2 emissions were  11 g/mi (3 percent) lower, and fuel economy was 0.6 mpg (3 percent) higher.
                 Adjusted COi Emissions
              Adjusted Fuel Economy
O
o
       700
       600
.2, --'  500
"
       400
                             Cars
          1975 1980 1985 1990 1995 2000 2005 2010
                       Model Year
O
Q_
                                                     T3
                                                      CD
       1975 1980 1985 1990 1995 2000 2005 2010
                  Model Year
       MY 2010 unadjusted laboratory composite values, which reflect vehicle design considerations only and do
not account for the many factors which affect real world CO2 emissions and fuel economy performance, were also at
an all-time low for CO2 emissions (313 g/mi) and a record high for fuel economy (28.4 mpg) since the database
began in 1975.
EPA-420-S-12-001
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                                      March 2012

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Highlight #2: MY 2010 truck market share increased by 5 percent compared to MY 2009, but is at
              the second lowest level since 1996.
        Light trucks, which include SUVs, minivans/vans, and pickup trucks, accounted for 36 percent of
        all light-duty vehicle sales in MY 2010.  This represents a 5 percent increase over MY 2009, but
        that was a year of market turmoil and MY 2009 truck share was 8 percent lower than MY 2008.
        Truck market share is now at the second lowest level since MY 1996 and 9 percent lower than the
        peak in MY 2004.  The MY 2011 light truck market share is projected to be 38 percent, based on
        pre-model year production projections by automakers.
       There were two changes to the database this year that affect truck market share. The first change, as
discussed above, is that most small, 2 wheel drive SUVs from MY 1975-2011 have been reclassified from trucks to
cars. This lowers the absolute truck share, particularly since the mid-1980s when SUV sales began to increase
rapidly, so truck share values in this report should not be compared to those in past versions of this report.  For
example, for MY 2010 data in this report, nearly 1.1 million vehicles are reclassified from trucks to cars, representing
a 10 percent absolute change in both the car and truck production share.  The second change, also discussed above, is
that, for the first time, the preliminary data for MY 2011 include MDPVs. EPA does not have data for MDPVs for
MY 1975-2010, so there is a small discontinuity in the database beginning in MY 2011. The projected production
volume for MDPVs in MY 2011 is approximately 10,000 vehicles, which increases the projected truck share of the
overall fleet in MY 2011 by less than 0.1 percent.

                               Production Share by Vehicle Type
               100%
                80%
           ro   60%
           OD
           o
           
           "   40%
                20%
                 0%
                                       Cars (Including Non-Truck SUVs)
                     1975    1980    1985    1990    1995    2000   2005    2010
                                            Model Year
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March 2012

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Highlight #3:  MY 2010 weight and power increased from MY 2009, but decreased relative to MY 2008.
        MY 2010 vehicle weight averaged 4002 pounds, an increase of 85 pounds compared to MY 2009,
        but the second lowest average weight since MY 2004. The average car and truck weight both
        increased by about 25 pounds each, and the remaining difference was due to higher truck market
        share.  In MY 2010, the average vehicle power was 214 horsepower, an increase of 6 horsepower
        since MY 2009, but lower than in MY 2007-2008.  Car power increased slightly and truck power
        was unchanged, so the primary factor in increasing the  overall power level was higher truck
        market share. Estimated MY 2010 O-to-60 acceleration time decreased slightly to 9.6 seconds.
                            Weight, Horsepower and O-to-60 Performance
                           4000
                           3800
                           3600
                           3400
                            220
                            200
                            180
                            160
                            140
                            120
                             14
                             13
                             12
                             11
                             10
                             9
Weight (Ib)
                                1975  1980  1985  1990  1995  2000  2005 2010
Horsepower
                                1975  1980  1985  1990  1995  2000  2005 2010
O-to-60 Time
(seconds)
                                1975  1980  1985  1990  1995  2000  2005 2010
                                               Model Year

       Vehicle weight and performance are two of the most important engineering parameters that help determine a
vehicle's CO2 emissions and fuel economy. All other factors being equal, higher vehicle weight (which supports new
options and features) and faster acceleration performance (e.g., lower O-to-60 mile-per-hour acceleration time), both
increase a vehicle's CO2 emissions and decrease fuel economy.  Automotive engineers are constantly developing
more efficient vehicle technologies.  From MY 1987 through MY 2004, on a fleetwide basis, this technology
innovation was generally utilized to support market-driven attributes other than CO2 emissions and fuel economy,
such as vehicle weight, performance, and utility. Beginning in MY 2005, technology has been used to increase both
fuel economy (which has reduced CO2 emissions) and performance, while keeping vehicle weight relatively constant.

       Preliminary MY 2011 values suggest that average vehicle weight and performance will both increase, though
these projections are uncertain and EPA will not have final data until next year's report.
EPA-420-S-12-001
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Highlight #4: Most manufacturers increased fuel economy in MY 2010, resulting in lower COi
              emission rates.
        Ten of the 13 highest-selling manufacturers increased fuel economy (which also reduced CO2 g/mi
        emission rates) from MY 2009 to MY 2010, the last two years for which we have definitive data,
        and 4 manufacturers increased fuel economy by 1 mpg or more.
       Adjusted CO2 emissions and fuel economy values are shown for the 13 highest-selling manufacturers, which
accounted for 99 percent of the market in MY 2010, in order from lowest to highest CO2 emissions for MY 2010.
Manufacturers are defined in accordance with current NHTSA CAFE guidelines, and these definitions are applied
retroactively for the entire database back to 1975 for purposes of maintaining integrity of trends over time.  In MY
2010, the last year for which EPA has final production data, Hyundai had the lowest fleetwide adjusted composite
CO2 emissions performance, followed very closely by Kia and then Toyota. Hyundai and Kiatied for the highest
fleetwide adjusted composite fuel economy value.  Daimler had the highest CO2 emissions (and lowest fuel
economy), followed by Chrysler and Ford. Kia had the biggest improvement in adjusted CO2 (and fuel economy)
performance from MY 2009 to MY 2010, with a 37 g/mi reduction in fleetwide CO2 emissions (and 2.8 mpg fuel
economy improvement), followed by Hyundai (26 g/mi reduction in CO2 emissions) and Mazda (19 g/mi reduction in
CO2 emissions).

       Preliminary MY 2011 values suggest that 11 of the 13 manufacturers will improve further in MY 2011,
though these projections are uncertain and EPA will not have final data until next year's report.
                     MY 2009-2011 Manufacturer Fuel Economy and CO2 Emissions
                                      (Adjusted Composite Values)

MY2009
Manufacturer MPG
Hyundai
Kia
Toyota
Honda
VW
Mazda
Subaru
Nissan
BMW
GM
Ford
Chrysler
Daimler
All
25.1
24.2
25.4
24.6
23.8
23.2
22.6
23.6
21.9
20.6
20.3
19.2
19.5
22.4
MY2009
CO2 MY2010
(g/mi) MPG
355
367
349
361
379
383
393
377
407
432
437
464
457
397
27.0
27.0
25.4
24.9
25.0
24.4
23.4
23.1
22.1
21.3
20.4
19.5
18.9
22.6
MY2010
CO2 MY2011
(g/mi) MPG
329
330
350
357
363
364
379
384
404
418
435
455
471
394
27.5
27.2
25.1
25.7
25.2
25.0
23.9
24.2
23.0
20.6
21.3
19.7
20.0
22.8
MY2011
C02
(g/mi)
323
327
354
345
360
355
371
368
389
431
417
451
447
391
       EPA fuel economy and CO2 emissions data is based on model year production. This means that year-to-year
comparisons can be affected by longer or shorter vehicle model year designations by the manufacturers. Section VII
has greater detail on the fuel economy and CO2 emissions for these 13 manufacturers, as well as for these
manufacturers' individual makes (i.e., brands).
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Highlight #5:  Many new technologies are rapidly gaining market share.
        Several advancedpowertrain technologies are making significant inroads into the mainstream
        market. For example, in terms of market share, gasoline direct injection doubled in MY 2010 and
        is projected to triple from MY 2009-2011, turbocharging is projected to double in MY 2011,
        cylinder deactivation is projected to nearly double in MY 2011, and both 6-speed and 7-speed
        transmissions approximately doubled from MY 2009-2011. These and other technology trends
        help to explain the improvements in CO2 and fuel economy over the last seven years.
       Personal vehicle technology has changed significantly since the database began in MY 1975. New
technologies are continually being introduced into the marketplace, while older and less effective technologies are
removed from the market. For example, in MY 1975 most engines relied on carburetors to deliver fuel to the engine.
Carburetors were replaced by fuel injection systems in the 1980s. Now, in some vehicles, conventional fuel injection
systems are being replaced by gasoline direct injection systems.

       Understanding trends in these technologies and their relationship to CO2 emissions and fuel economy enables
a better understanding of the personal vehicle market. Below is a snapshot of several important technologies for
seven selected model years.  The first column of data is from MY 1975, the first year of data for this report. The
next two years, MY 1987 and 2004, were historical inflection points for CO2 emissions and fuel economy (see
Highlight #1). The table also contains data from several recent years.
Light Duty Vehicle Characteristics for Seven Model Years

Adjusted CO2 Emissions (g/mi)
Adjusted Fuel Economy (MPG)
Weight (Ib)
Horsepower
0-to-60Time (sec.)
Truck Production
Four-Cylinder Engine
Eight-Cylinder Engine
Multi-Valve Engine
Variable Valve Timing
Cylinder Deactivation
Gasoline Direct Injection
Turbocharged or Supercharged
Manual Transmission
Continuously Variable Transmission
6 Speed Transmission
7+ Speed Transmission
Hybrid
Diesel
1975
681
13.1
4060
137
14.1
19%
20%
62%
-
-
-
-
-
23.0%
-
-
-
-
0.2%
1987
405
22.0
3221
118
13.1
27%
55%
15%
-
-
-
-
-
29.1%
-
-
-
-
0.3%
2004
461
19.3
4111
211
9.9
45%
28%
24%
62%
39%
-
-
2.9%
6.8%
1.2%
3.0%
0.2%
0.5%
0.1%
2008
424
21.0
4085
219
9.7
39%
38%
17%
76%
58%
6.7%
2.3%
3.3%
5.2%
7.9%
19.4%
2.0%
2.5%
0.1%
2009
397
22.4
3917
208
9.7
31%
51%
12%
84%
72%
7.4%
4.2%
3.5%
4.7%
9.5%
24.7%
2.6%
2.3%
0.5%
2010
394
22.6
4002
214
9.6
36%
50%
14%
85%
84%
6.4%
8.3%
3.5%
3.8%
10.9%
38.1%
2.8%
3.8%
0.7%
2011
391
22.8
4084
228
9.3
38%
47%
16%
85%
94%
11.1%
13.7%
7.4%
5.1%
10.8%
52.4%
4.9%
4.0%
0.6%
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Additional Notes on Data Contained in This Report

       This report supersedes all previous reports in this series. Users of this report should rely exclusively on data
in this latest report, which covers MY 1975 through 2011, and not make comparisons to data in previous reports in
this series.  There are several reasons for this.

       One, EPA revised the methodology for estimating "real-world" (i.e., label) fuel economy values in December
2006. Every adjusted (ADJ) fuel economy value in this report for 1986 and later model years is lower than given in
reports in this series prior to the 2007 report. See Appendix A for more in-depth discussion of the current
methodology and how it affects both the adjusted fuel economy values for individual models and the historical fuel
economy trends database. This same methodology is used to calculate adjusted CO2 emissions values as well. Two,
as discussed above, for the first time in this version of the report, EPA reclassifies most small, 2 wheel drive SUVs
from trucks to cars for the entire MY 1975-1011  database.  Beginning with this report, all car/truck classifications in
this database are consistent with determinations made by NHTSA for CAFE standards beginning in MY 2011 and
EPA for CO2 emissions standards for MY 2012 and later. Three, when EPA changes a manufacturer or vehicle make
definition to reflect a change in the industry's current financial arrangements, EPA makes the same adjustment in the
historical database as well. This maintains a consistent manufacturer/make definition over time,  which allows the
identification of long-term trends.  On the other hand, it means that the database does not necessarily reflect actual
past financial arrangements. For example, the 2011 database, which includes data for the entire time series MY 1975
through 2011, accounts for all Chrysler vehicles in the 1975-2011 timeframe under the Chrysler manufacturer
designation, and no longer reflects the fact that Chrysler was combined with Daimler for several  years.

       Through MY 2010, the CO2 emissions, fuel economy, vehicle characteristics, and vehicle production volume
data used for this report were from the formal end-of-year submissions from automakers obtained from EPA's fuel
economy database that is used for CAFE compliance purposes. For MY 2011, EPA has exclusively used confidential
pre-model year production volume projections  from automaker label submissions.  Accordingly,  MY 2011
projections are uncertain. Historically, the differences between the initial estimates based on vehicle production
projections and later,  final values have  ranged between 0.4 mpg lower to 0.6 mpg higher. But, the market turmoil in
MY 2009 was a major exception in this regard, as the final MY 2009 value from the 2010 report was 1.3 mpg higher
than the preliminary value for MY 2009 from the 2009 report based on projected production volumes.

       The database in this report includes data  from vehicles certified to operate on gasoline or diesel fuel, from
laboratory testing with test fuels as defined in EPA test protocols (e.g., with zero ethanol). It includes data from
ethanol flexible fuel vehicles, which can operate  on gasoline or an 85 percent ethanol/15 percent gasoline blend or
any mixture in between, operated on gasoline only. Data from the small number of vehicles that are certified to
operate only on alternative fuels or are  expected to operate frequently on alternative fuels (such as plug-in hybrid
electric vehicles or dual-fuel compressed natural  gas vehicles) are not included in this database because they currently
represent less than 0.2 percent of all sales and because the emissions and fuel economy data from alternative fuel
vehicles raise issues with respect to the metrics that are used in this report.

       Vehicle population data in this report represent production delivered for sale in the  U.S., rather than actual
sales data.  Automakers submit production data in formal end-of-year CAFE compliance reports  to EPA, which is the
basis for this report. Accordingly, the production data in this report may differ from sales data reported by press
sources, because not all vehicles produced for sale in a given model year will necessarily be sold in that model year.
In addition, the data presented in this report are tabulated on a model year, not calendar year, basis.
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For More Information

Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975 through 2011
(EPA-420-R-12-001) is available on the Office of Transportation and Air Quality's (OTAQ) Web site at:

       www. epa.gov/otaq/fetrends .htm

Printed copies are available from the OTAQ library at:

       U.S. Environmental Protection Agency
       Office of Transportation and Air Quality Library
       2000 Traverwood Drive
       Ann Arbor, MI 48105
       (734)214-4311


A copy of the Fuel Economy Guide giving city and highway fuel economy data for individual models is available at:

       www.fueleconomy.gov

or by calling the U.S. Department of Energy at (800) 423-1363.


For information about EPA's Greenhouse Gas Emissions Standards, see:

       http://epa.gov/otaq/climate/regulations.htm


For information about the EPA/Department of Transportation (DOT) Fuel Economy and Environment Labels, see:

       http: //epa.gov/otaq/carlabel
For information about DOT's Corporate Average Fuel Economy (CAFE) program, including a program overview,
related rulemaking activities, and summaries of the fuel economy performance of individual manufacturers since
1978, see:

       http://www.nhtsa.dot.gov/fuel-economy
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