# Light

- Duty Automotive T echnology and

Fuel Economy T rends:

1975 through 2007

# Light

- Duty Automotive T echnology and

Fuel Economy T rends:

1995 through 2007

Compliance and Innovative Strategies Division

and

T ransportation and Climate Division

Office of T ransportation and Air Quality

U.S. Environmental Protection Agency

NO TICE

T

his tec hnical report does not necessarily represent final EP A decisions or

positions. It is intended to present tec hnical analy sis of issues using dat a

that are cur rently a v ailable. T he purpose in the release of suc h reports is to

f acilit ate the e x

c

hange of tec hnical inf ormation and to inf orm the public of

tec hnical de v elopments

.

EP A420-R-07-008

September 2007

## Table of Contents

Page

Number

I. Executive Sum m a ry

........................................................................................................... i

II. Introduction

.................................................................................................................. ....... 1

III. General Car and Truck Trends

........................................................................................... 6

IV. Trends by Vehicle Type, Size and W e ight

........................................................................ 18

V. Technology Trends

.......................................................................................................... 36

VI. Marketing Groups

......................................................................................................... ... 67

VII. Characteristics of Fleets Com p rise d of Existing Fuel-Efficient Vehicles

........................ 77

VIII. References

. . . . .................................................................................................... .......... 87

Appendixes

. . . . . . ..................................................................................................... A -Q

## Table of Contents, continued

Appendixes

APPENDIX A - Database Details and Calculation Methods

APPENDIX B - Model Year 2007 Nam e plate Fuel Econom y Listings

APPENDIX C - Fuel Econom y Distribution Data

APPENDIX D - Data Stratified by Vehicle Type

APPENDIX E - Data Stratified by Vehicle Type and Size

APPENDIX F - Car Data Stratified by EPA Car Class

APPENDIX G - Data Stratified by Ve hicle Type and W eight Class

APPENDIX H - Data Stratified by Vehicle Type and Drive Type

APPENDIX I - Data Stratified by Vehicle Type and Transm ission Type

APPENDIX J - Data Stratified by Vehicle Type and Cylinder Count

APPENDIX K - Data Stratified by Vehicle Type , Engine Type and Valves Per Cylinder

APPENDIX L - Data Stratified by Vehicle Type and Marketing Group

APPENDIX M - Fuel Econom y by Marketing Group, Vehicle Type and W e ight Class

APPENDIX N - Fuel Econom y and Ton-MPG by Marketing Group, Vehicle Type and Size

APPENDIX O - MY2007 Fuel Econom y by Vehicl e Type, W e ight and Marketing Group

APPENDIX P - Data Stratified by Marketing Group and Vehicle Type

APPENDIX Q - Characteristics of Fleets Co m p rised of Fuel Efficient Vehicles

## I. Executive Summary

Introduction

This report sum m arizes key trends in fuel econom y and technology usage related to

m odel year (MY) 1975 through 2007 light-duty vehicles sold in the United States. Light-duty

vehicles are those vehicles that EPA classif i es as cars or light-duty trucks (sport utility vehicles,

vans, and pickup trucks with less than 8500 pounds gross vehicle weight ratings).

Since 1975, overall new light-duty vehicle fuel econom y has m oved through four phases:

1. a rapid increase from 1975 through the early 1980s,

2. a slower increase until reaching its peak in 1987,

3. a gradual decline until 2004, and

4. an increase in 2005 and 2006, with 2007 levels projected to be sim ilar to 2006.

The projected average MY2007 light-duty vehicle fuel econom y, based in large part on

pre-m odel year sales projections from autom akers, is 20.2 m iles per gallon (m pg). The MY2006

value is also 20.2 m pg. There is greater confidence in the MY2006 value as the database for

2006 includes form al sales data for about 70% of the MY2006 fleet. The 20.2 m pg value for

m odel years 2006 and 2007 represents a 0.9 m pg, or 5%, increase over the 19.3 m pg value for

2004, which was the lowest fuel econom y value since 1980.

The fuel econom y values in this report are either adjusted (ADJ) EPA “real-world”

estim ates provided to consum ers, or unadjusted EPA laboratory (LAB) values. Most of the data

is presented in adjusted values. Either adjusted or laboratory fuel econom y m ay be reported as

city, highway, or, m o st com m only, as composite (com bined city/highway, or COMP). In 2006,

EPA revised the m e thodology by which EPA estim ates adjusted fuel econom y to better reflect

changes in driving habits and other factors th at affect fuel econom y such as higher highway

speeds, m o re aggressive driving, and greater use of air conditioning. This is the first report in

this series to reflect this new real-world fuel econom y m e thodology, and every adjusted fuel

econom y value in this report for 1986 and later m odel years is lower than previously reported.

To reflect the fact that these changes did not occur overnight, these new downward adjustm ents

are phased in, gradually, beginning in 1986, and for 2005 and later m odel years the new adjusted

com posite (com bined city/highway) values are, on average, about 6% lower than under the

m e thodology used by EPA in previous reports in this series. See Appendix A for m o re details.

Because the underlying m e thodology for genera ting unadjusted laboratory fuel econom y values has not changed since this series began in the m i d-1970s, they provide an excellent basis

for com p aring long-term fuel econom y trends from the perspective of vehicle design, apart from

the factors that affect real-world fuel econom y that are reflected in the adjusted fuel econom y

values. For 2005 and later m odel years, unadjusted laboratory com posite fuel econom y values

are, on average, about 25% greater than adjusted com posite fuel econom y values.

The Departm e nt of Transportation’s Nationa l Highway Traffic Safety Adm i nistration

(NHTSA) has the overall responsibility for the Corporate Average Fuel Econom y (CAFE)

program

. For 2007, the CAFE standards are 27.5 m pg for cars and 22.2 m pg for light trucks.

EPA provides laboratory com posite 55/45 fuel econom y data, along with alternative fuel vehicle

credits and test procedure adjustm e nts, to NHTSA for CAFE enforcem ent. Accordingly, current

NHTSA CAFE values are a m i nim um of 25% higher than EPA adjusted fuel econom y values.

i

## Importance of Fuel Economy

Fuel econom y continues to be a m ajor area of public and policy interest for several

reasons, including:

1. Fuel econom y is directly related to energy security because light-duty vehicles

account for approxim a tely 40 percent of all U.S. oil consum ption, and m u ch of

this oil is im ported.

2. Fuel econom y is directly related to the cost of fueling a vehicle and is of great

interest when crude oil and gasoline prices rise.

3. Fuel econom y is directly related to em issions of greenhouse gases (i.e., carbon

dioxide). Light-duty vehicles contri bute about 20 percent of all U.S. carbon

dioxide em issions.

Characteristics of Light Duty Vehicles for Four Model Years

**1975 1987**  **1997 2007** 

**Adjusted Fuel Economy (mpg) 13.1**  **22.0 20.1**  **20.2**

**Weight (lbs.) 4060**  **3221 3727**  **4144**

**Horsepower 137**  **118 169**  **223**

**0 to 60 Time (sec.) 14.1**  **13.1 11.0**  **9.6**

**Percent Truck Sales 19%**  **28% 42%**  **49%**

**Percent Front-Wheel Drive 5%**  **58% 56%**  **51%**

**Percent Four-Wheel Drive 3%**  **10% 19%**  **28%**

**Percent Multi-Valve Engine**

**- -**  **40% 70%** 

**Percent Variable Valve Timing**

**- -**  **- 59%** 

**Percent Cylinder Deactivation**

**- -**  **- 8%** 

**Percent Turbocharger -**  **- 0.5%**  **3%**

**Percent Manual Transmission 23%**  **29% 14%**  **8%**

**Percent Continuously Variable Trans**

**- -**  **- 7%** 

**Percent Hybrid**

**- -**  **- 2.2%** 

**Percent Diesel 0.2%**  **0.3% 0.1%**  **0.1%**



## ii

## Highlight #1: Fuel Economy Increases in 2005 and 2006 Reverse the Long-Term Trend of

Declining Fuel Economy From 1987 Through 2004.

Overall fuel economy increased 0.9 mpg, or 5%, from 19.3 mpg in MY2004 to 20.2 mpg

in MY2006. Fuel economy for both cars and trucks is projected to increase for MY2007.

However, due to a slight increase in projected truck market share, the overall value for

MY2007 is also projected to be 20.2 mpg. The increases in 2005 and 2006 are the first

consecutive annual increases in fuel economy since the mid-1980s. This reverses a long

trend of slowly declining fuel economy since the 1987 peak.

Since 1975, the fuel econom y of the com b ined car and light truck fleet has m oved

through several phases: (1) a rapid increase from 1975 to the early 1980s, (2) a slow increase

extending to the fuel econom y peak of 22.0 m pg in 1987, (3) a gradual decline from the peak to

19.3 m pg in 2004, and (4) consecutive annual increases in 2005 and 2006, growing to 20.2 m pg

in 2006, with the sam e value projected for 2007.

The 20.2 m pg value for m odel years 2006 and 2007 is 1.8 m pg below the peak of 22.0

m pg in MY1987. But, it is im portant to note that two-thirds of this difference is due to the new

m ethodology for calculating adjusted fuel econom y values that is gradually phased in over the

1986 to 2005 tim efram e

. Based on the laboratory com posite 55/45 fuel econom y values, which

are not affected by the new m e thodology for calculating adjusted fuel econom y values, the

MY2006 and MY2007 value of 25.3 m pg is 0.6 m pg below the peak of 25.9 m pg in 1987.

MY2007 cars are projected to average 23.4 m pg and MY2007 light trucks are estim ated

to average 17.7 m pg, both 0.1 m pg higher than MY2006. Most of the increase in overall fuel

econom y since 2004 has been due to higher truck fuel econom y, as truck fuel econom y has

increased by 1.0 m pg since 2004 while car fuel econom y has increased by 0.3 m pg (prior to

MY2007, the overall fleetwide fuel econom y increase had also been aided by a slightly higher

car m arket share). The recent increase in truck fuel econom y is due, in part, to higher truck

CAFE standards, which have risen from 20.7 m pg in 2004 to 22.2 m pg in 2007.

Adjusted Fuel Economy by Model Yea r

(Annual Data)

Adjusted MPG



## 30

1970 1975 1980 1985 1990 1995 2000 2005 2010 Cars

Truc k s Both 

## 25

20

15

10

iii

## Highlight #2: Trucks Continue To Represent About Half of New Vehicle Sales.

Sales of light trucks, which include sport utility vehicles (SUVs) , vans, and pickup trucks,

have accounted for about 50 percent of the U.S. light-duty vehicle market since MY2002.

After two decades of constant growth, light truck market share has been relatively stable

for the last six years.

Historically, growth in the light truck m arket was prim arily driven by the explosive

increase in the m a rket share of SUVs. The SUV m a rket share increased from less than 10

percent of the overall new light-duty vehicle m ark et in MY1990 to about 30 percent of vehicles

built each year since 2003. By com p arison, m arket shares for both vans and pickup trucks have

declined slightly since 1990. The increased overall m arket share of light trucks, which in recent

years have averaged 5-7 m pg lower than cars, accounted for m u ch of the decline in fuel econom y of the overall new light-duty vehicle fleet from MY1987 through MY2004.

S a l e s Fr a c t i on by V e hi c l e Ty pe

( A nnua l D a t a )

0% 20 % 40 % 60 % 80 % 100 % M ar ket S h are

Pi c k u p Va n SU V Ca r

19 75 19 80 19 85 19 90 19 95 20 00 20 05

M ode l Y e a r



## iv

## Highlight #3: Technological Innovation in 2005 and 2006 Was Utiliz ed for Higher Fuel

Economy, Reversing the Long-Term Trend of Increasing Vehicle Attributes Such as

Weight and Performance.

Automotive engineers are constantly developing more advanced and efficient vehicle

technologies. From 1987 through 2004, on a fleet wide basis, this technology innovation

was utilized to support market-driven attributes other than fuel economy, such as vehicle

weight (which supports vehicle content and features)

, performance, and utility. This

long-term trend was reversed in model years 2005 and 2006, as technology was used to

increase fuel economy by 0.9 mpg. The current projection for MY2007 is an increase in

market-driven attributes with no change in fuel economy, but this is subject to change

when EPA obtains formal 2007 sales data.

Vehicle weight and perform ance are two of the m o st im portant engineering param eters

that determ ine a vehicle = s fuel econom y. All other factors being equal, higher vehicle weight

(which supports new options and features) and faster acceleration perform ance (e.g., lower 0-to

60 m ile-per-hour acceleration tim e), both decrease a vehicle = s fuel econom y. Average vehicle

weight and perform a nce had increased steadily from the m i d-1980s through 2004.

Average light-duty vehicle weight droppe d in both m odel years 2005 and 2006, with a

slight increase in weight of cars m o re than o ffset by a larger decrease in truck weight and a

decrease in truck m arket share. Average weight is projected to grow again in MY2007 to the

highest level ever. Average fleetwide perfor m a nce was essentially unchanged in both 2005 and

2006, but is also projected to increase to record levels in MY2007. The validity of these

projections will be conf irm ed when EPA obtains f o rm al vehicle sales data af ter the end of

MY2007.

Weight and Performance

(Annual Data)

30 0 0 35 0 0 4 0 0 0 45 0 0 W e ight (lbs.)

9 1 0 1 1 1 2 1 3 1 4 15 0 to 60 Time (sec.)

We ig h 0 to 60 Ti m e

1975 1980 1985 1990 1995 2000 2005



### Mode l Ye a r



## v

## Marketing Group Fuel Economy for Three Model Years Highlight #4: Differences Betw een Marketing Group Fuel Economies are Narrow i ng.

In 1987, when industry-wide fuel economy peaked, some major marketing groups had

average fuel economies 6 to 8 mpg higher than other top marketing groups. For

MY2007, the maximum difference between major marketing groups is estimated to be 4.6

mpg, with a typical difference between higher and lower fuel economy marketing groups

being 3 to 4 mpg.

For MY2007, the eight highest-selling m arketing groups (that account for over 95

percent of all sales) fall into three fuel econom y groupings: Honda, Toyota, and Hyundai-Kia

(HK) have estim ated fuel econom ies of 22.7 to 22.9 m pg; Volkswagen and Nissan have

projected fuel econom ies of 20.6 to 21.4 m pg; and General Motors, Ford, and Daim lerChrysler

have estim ated fuel econom ies of 18.3 to 19.4 m pg. Note that these adjusted fuel econom y

values for m arketing groups can not be directly com p ared to those in last year’s report, since this

year’s report uses the new m e thodology where adjusted fuel econom y values since 2005 are, on

average, about 6% lower than in previous reports.

Each of these m a rketing groups has lower average fuel econom y today than in 1987.

Since then, the differences between m a rketing group fuel econom ies have narrowed

considerably, with som e of the higher m pg m a rketing groups in 1987 showing larger fuel

econom y decreases since 1987. Only one m a rketing group, Toyota, shows a slight increase in

average fuel econom y since 1997. For MY2007, Volkswagen is the only one of the eight

highest-selling m arketing groups to have a truck m arket share of less than 40 percent.

Marketing Group Fuel Economy for Three Model Years

A d j u st ed C o mposit e M P G

30

25

20

15

10

5

0

V W HK Toy ota Honda DC Ford G M Nis s a n 2007 1997 1987



## vi

## Important Notes With Respect to the Data Used in This Report

Most of the fuel econom y values in this report are a single adjusted com posite (com bined

city/highway) fuel econom y value, based on the real-world estim ates for city and highway fuel

econom y provided to consum ers on new vehicle labels, in the EPA/DOE Fuel Economy Guide,

and in EPA = s Green Vehicle Guide

.

It is im portant to note that EPA revised the m ethodology for estim ating real-world fuel

econom y values in Decem ber 2006. This is the first report in this series to reflect this new realworld fuel econom y m e thodology, and every adjusted (ADJ) fuel econom y value in this report

for 1986 and later m odel years is lower than given in previous reports in this series.

Accordingly, adjusted fuel econom y values for 1986 and later m odel years should not be

com p ared with the corresponding values from previous reports. These new downward

adjustm ents are phased in, linearly, beginning in 1986, and for 2005 and later m odel years the

new adjusted com posite (com bined city/highway) values are, on average, about 6% lower than

under the m e thodology previously used by EPA. See Appendix A for m o re in-depth discussion

of this new m e thodology and how it affects both th e adjusted fuel econom y values for individual

m odels and the historical fuel econom y trends database.

In som e tables and figures in this report, a single laboratory com posite (com bined

city/highway) 55/45 value is also shown. Because the underlying m e thodology for generating

and reporting laboratory fuel econom y values has not changed since this series began in the m i d

1970s, these laboratory fuel econom y values provide an excellent basis for com p aring long-term

fuel econom y trends from the perspective of vehi cle design, apart from the factors that affect

real-world fuel econom y that are reflected in the adjusted fuel econom y values. For 2005 and

later m odel years, laboratory com posite fuel econom y values are, on average, about 25% greater

than adjusted com posite fuel econom y values.

Form al Corporate Average Fuel Econom y (CAFE) com p liance data as reported by the

Departm ent of Transportation’s National Highway Traffic Safety Adm i nistration (NHTSA) does

not correlate precisely with either the adjusted or laboratory fuel econom y values in this report.

W h ile EPA’s laboratory com posite 55/45 fuel econom y data form s the cornerstone of the CAFE

com p liance database, NHTSA m u st also include credits for alternative fuel vehicles and test

procedure adjustm ents (for cars only) in the o fficial CAFE calculations. Accordingly, NHTSA

CAFE values are at least 25% higher than EPA adjusted fuel econom y values for m odel years

2005 through 2007.

In general, car/truck classifications in this database parallel classifications m ade by

NHTSA for CAFE purposes and EPA for vehicle em issions standards. However, this report

relies on engineering judgm ent, and typically there are a few cases each m odel year where the

m ethodology used for classifying vehicles for this report results in differences in the

determ ination of whether a given vehicle is classi fied as a car or a light truck. See Appendix A

for a list of these exceptions.

The data presented in this report were tabulated on a m odel year basis, but m any of the

figures in this report use three-year m oving averages that effectively sm ooth the trends, and

these three-year m oving averages are tabulated at the m i dpoint. For exam ple, the m i dpoint for

m odel years 2005, 2006, and 2007 is MY2006. Figures are based on annual data unless

otherwise noted.

vii

## All average fuel econom y values were calculated using harm onic, rather than

arithm etical, averaging, in order to m aintain m athem atical integrity. See Appendix A.

The EPA fuel econom y database used to generate the fuel econom y trends database in

this report was frozen in February 2007, yielding additional data beyond that used in last year’s

report for m odel years 2004 through 2007, although additional data for MY2006 was added in

April 2007.

Through MY2005, the fuel econom y, vehicle characteristics, and sales data used for this

report were from the form al end-of-year subm issi ons from autom a kers obtained from EPA’s fuel

econom y database that is used for CAFE com p liance purposes. Accordingly, values for all

m odel years up to 2005 can be considered final.

For MY2006, the data used in this report is based on a database where about 70% of the

total sales are from form al end-of-year CAFE subm issions by autom a kers, and about 30% are

f r om conf idential pre-m odel year sales projections subm itted to the Agency by the autom akers,

with these latter projections updated based on actual 2006 sales data reported in trade

publications. EPA has a high level of confidence in the data for MY2006, given that 70% of the

2006 data is based on actual CAFE reports. It is noteworthy that the 25.3 m pg laboratory fuel

econom y value for MY2006 in this report is 0.7 m pg higher than the projected 24.6 m pg laboratory fuel econom y value for MY2006 in the 2006 report. This suggests that sustained,

higher gasoline prices have led to actual 2006 sales that differ from the projected 2006 sales

provided to EPA by autom a kers in 2005.

For MY2007, EPA has exclusively used confidential pre-m odel year sales projections,

updated based on actual sales for the first 7 m onths of m odel year 2007 (October 2006 through

April 2007). MY2007 projections are m o re uncertain, particularly given the changes in the

autom o tive m arketplace driven by higher fuel prices and other factors. For m odel years 1998

through 2005, the final laboratory fuel econom y values for a given m odel year have varied from

0.4 m pg lower to 0.3 m pg higher com p ared to original estim ates for the sam e m odel year that

were based exclusively on projected sales.

viii

## For More Information

Light-Duty Automotive Technology and Fuel Economy Trends: 1975 through 200 7

(EPA420-R-07-008) is available on the Office of Transportation and Air Quality = s (OTAQ) W e b

site at:

http://www.epa.gov/otaq/fetrends.htm

Printed copies are available from the OTAQ library at:

U.S. Environm ental Protection Agency

Of f i ce 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 econom y data for individual

m odels is available at:

http://www.fueleconom y.gov

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

EPA's Green Vehicle Guide providing inform ation about the air pollution em issions and fuel

econom y perform a nce of individual m odels is available on EPA = s web site at:

http://www.epa.gov/greenvehicles/

For inform ation about the Departm e nt of Tr ansportation (DOT) Corporate Average Fuel

Econom y (CAFE) program , including a program overview, related rulem aking activities,

research, and sum m aries of individual m anufacturer = s fuel econom y perform a nce since 1978,

see:

http://www.nhtsa.dot.gov/ and click on “Fuel Econom y”

ix

## II. Introduction

Light-duty autom o tive technology and fuel econom y trends are exam ined here, as in the

preceding reports in this series [1-33] * 

## , using the latest and m o st com p lete EPA data available.

W h en com p aring data in this and previous reports, please note that revisions are m ade for

som e prior m odel years for which m o re com p lete and accurate sales and fuel econom y data have

becom e available. In addition, changes have been m ade periodically in the way EPA calculates

adjusted fuel econom y values which m eans it is not appropriate to com p are adjusted fuel

econom y values from this report with others in this series.

The EPA fuel econom y database used to generate the fuel econom y trends database in

this report was frozen in February 2007, yielding additional data beyond that used in last year’s

report for m odel years 2004 through 2007, though additional data for MY2006 was added in

April 2007.

Through MY2005, the fuel econom y, vehicle characteristics, and sales data used for this

report were from the form al end-of-year subm issi ons from autom a kers obtained from EPA’s fuel

econom y database that is used for CAFE com p liance purposes. For MY2006, the data used in

this report is based on a database where about 70% of the total sales are from form al end-of-year

CAFE subm issions by autom a kers, and about 30% of the total sales are based on confidential

pre-m odel year sales projections subm itted to the Agency by the autom akers, with these latter

projections updated based on actual 2006 sales data reported in trade publications. For MY2007,

EPA has exclusively used confidential pre-m odel year sales projections, updated based on actual

sales for the first 7 m onths of m odel year 2007 (October 2006 through April 2007).

Accordingly, values for all m odel years up to 2005 can be considered final. EPA has a

high level of confidence in the data for MY2006, given that 70% of the 2006 data is based on

actual CAFE reports. MY2007 projections are m o re uncertain, particularly given the changes in

the autom o tive m arketplace driven by higher fuel prices and other factors. Over the last several

years, the final fuel econom y values for a given m odel year have varied from 0.4 m pg lower to

0.3 m pg higher com p ared to original estim ates for the sam e m odel year that were based

exclusively on projected sales.

All fuel econom y averages in this report are sales-weighted harm onic averages. In prior

reports in this series, up to and including the one for MY2000, the only fuel econom y values

used in this series were the laboratory-based city, highway, and com posite (com bined

city/highway) m pg values

C the sam e ones that are used as the basis for com p liance with the

fuel econom y

__________ * Num b ers in brackets denote references listed in the references section of this report.

1

## standards and the gas guzzler tax. Since the laboratory m pg values tend to over predict the m pg achieved in actual use, adjusted m pg values are used for the Governm ent = s fuel econom y

inform ation program s: the Fuel Economy Guide and the Fuel Economy Labels that are on new

vehicles and in EPA = s Green Vehicle Guide.

Starting with the report issued for MY2001, this series of reports has provided fuel

econom y trends in adjusted m pg values in addition to the laboratory m pg values. In this way,

the fuel econom y trends can be shown for both laboratory m pg and m pg values which can be

considered to be an estim ate of on-road m pg. In the tables, these two m pg values are called

A Laboratory MPG @ and A Adjusted MPG, @ and abbreviated A LAB @ MPG and A ADJ @ MPG.

W h ere only one m pg value is presented in this report, it is the A adjusted com posite” fuel

econom y value. This value represents a com b ined city/highway fuel econom y value, and is

based on equations (see Appendix A) that allow a co m putation of adjusted city and highway fuel

econom y values based on laboratory city and highway fuel econom y test values.

It is im portant to note that EPA revised the m ethodology by which EPA estim ates realworld fuel econom y values in Decem ber 2006. This is the first report in this series to reflect this

new real-world fuel econom y m e thodology, and every adjusted (ADJ) fuel econom y value in this

report for 1986 and later m odel years is lower than given in previous reports in this series.

Accordingly, adjusted fuel econom y values for 1986 and later m odel years should not be

com p ared with corresponding values from previous reports. These new downward adjustm e nts

are phased in, linearly, beginning in 1986, and for 2005 and later m odel years the new adjusted

com posite values are, on average, about 6% lower than under the m ethodology previously used

by EPA. See Appendix A for m ore in-depth discussion of this new m e thodology and how it

affects both the adjusted fuel econom y values fo r individual m odels and the historical fuel

econom y trends database.

The data presented in this report were tabulated on a m odel year basis, but m any of the

figures in this report use three-year m oving averages which effectively sm ooth the trends, and

these three-year m oving averages are tabulated at their m i dpoint. For exam ple, the m i dpoint for

m odel years 2002, 2003, and 2004 is m odel year 2003 (See Table A-2, Appendix A). Use of

the three-year m oving averages results in an im provem ent in distinguishing real trends from

what m i ght be relatively sm all year-to-year variations in the data.

To f acilitate com p arison with data in previous reports in this series, m o st data tables

include laboratory 55/45 fuel econom y values as well as the adjusted city, highway, and

com posite fuel econom y values. Presenting both types of m pg values facilitates the use of this

report by those who study either type of fuel econom y m e tric.

2

## The fuel econom y values reported by the Departm e nt of Transportation (DOT) for

com p liance with the Corporate Average Fuel Econom y (CAFE) com p liance purposes are higher

than the data in this report for four reasons:

(1) the CAFE data do not include the EPA real world fuel econom y labeling adjustm e nt

factors for city and highway m pg,

(2) the CAFE data are increase d by special procedures for calculating the fuel economy of

dedicated alternative fueled vehicles (the fuel econom y of all dedicated alternative fuel vehicles

is calculated based on the assum p tion that the alternative fuel has a fuel content of .15 gallon of

fuel) and dual fueled vehicles (a m a nufacturer' s CAFE for each of its fleets can be increase d up to

1.2 m pg).

(3) the CAFE data reflect adjustm ents m ade to account for changes to test procedures for

cars, and

(4) there are som e slight differences in the way that vehicles are classified as cars and

trucks for this report com p ared to the way they are classified by DOT.

Accordingly, the fuel econom y values in this series of reports are always lower than those

reported by DOT. Table A-6, Appendix A, com p ares CAFE data reported by DOT with EPAadjusted and laboratory fuel econom y data.

Other Variables

All vehicle weight data are based on inertia we ight class (nom inally curb weight plus 300

pounds). For vehicles with inertia weights up to and including the 3000-pound inertia weight

class, these classes have 250-pound increm ents. For vehicles above the 3000-pound inertia

weight class (i.e., vehicles 3500 pounds and above), 500-pound increm ents are used.

All interior volum e data for cars built after m odel year 1977 are based on the m etric used

to classify cars for the DOE/EPA Fuel Economy Guide

. The car interior volum e com b ines the

passenger com p artm ent and trunk/cargo space. In the Fuel Economy Guide , interior volum e is

undefined for the two-seater class; for this series of reports, all two-seater cars have been

assigned an interior volum e value of 50 cubic feet.

The light truck data used in this series of re ports includes only vehicles classified as light

trucks with gross vehicle weight ratings ( GVW R) up to 8500 pounds (lb). Vehicles with GVW R

above 8500 lb are not included in the database used for this report. Om itting these vehicles

influences the overall averages for all variables studied in this report. The m o st recent estim ates

we have m a de for the im pact of these greater than 8500 lb GVW R vehicles was m a de for m odel

year 2001. In that year, there were roughly 931,000 vehicles above 8500 lb GVW R. A

substantial fraction (42 percent) of the MY2001 vehicles above 8500 lb GVW R were powered

by diesel engines, and three-fourths of the vehicles over 8500 lb GVW R were pickup trucks.

Adding in the trucks above 8500 lb GVW R would have increased the truck m a rket share for that

year by three percentage points.

3

## Based on a lim ited am ount of actual laboratory fuel econom y data, MY2001 trucks with

GVW R greater than 8500 lb GVW R are estim ated to have fuel econom y values about 14 percent

lower than the average of trucks below 8500 lb GVW R. The com b ined fleet of all vehicles

under 8500 lb GVW R and trucks over 8500 lb GVW R is estim ated to average a few percent less

in fuel econom y com p ared to that for just the vehicles with less than 8500 lb GVW R.

In addition to fuel econom y, som e tables in this report contain alternate m easures of

vehicle fuel efficiency as used in reference 17.

A Ton-MPG @ is defined as a vehicle = s m pg m u ltiplied by its inertia weight in tons. This

m etric provides an indication of a vehicle = s ability to m ove weight (i.e., its own plus a nom inal

payload). Ton-MPG is a m easure of powertrain/dr ive-line efficiency. Just as an increase in

vehicle m pg at constant weight can be considered an im provem ent in a vehicle = s efficiency, an

increase in a vehicle = s weight-carrying capacity at constant m pg can also be considered an

im provem ent.

A Cubic-feet-MPG @ for cars is defined in this report as the product of a car = s m pg and its

interior volum e, including trunk space. This m etric associates a relative m easure of a vehicle = s ability to transport both passengers and their cargo. An increase in vehicle volum e at constant

m

pg could be considered an im provem ent just as an increase in m pg at constant volum e can be.

A Cubic-feet-ton-MPG @ is defined in this report as a com b ination of the two previous

m etrics, i.e., a car = s m pg m u ltiplied by its weight in tons and also by its interior volum e. It

ascribes vehicle utility to the ability to m ove both weight and volum e.

This report also includes an estim ate of 0-to-60 m ph acceleration tim e, calculated from

engine rated horsepower and vehicle in ertia weight, from the relationship:

t = F (HP/W T ) -f



## where the values used for F and f coefficients are .892 and .805 respectively for vehicles with

autom atic transm issions and .967 and .775 respectively for those with m anual transm issions [34].

Other authors [35, 36, and 37] have evaluated the relationships between weight, horsepower,

and 0-to-60 acceleration tim e and have calculated and published slightly different values for the

F and f coefficients. Since the equation form and coefficients were developed for vehicles with

conventional powertrains with gasoline-fueled engines, we have not used the equation to

estim ate 0-to-60 tim e for vehicles with hybrid powertrains or diesel engines. Published values

are used for these vehicles instead.

The 0-to-60 estim ate used in this report is intended to provide a quantitative tim e "index"

of vehicle perform ance capability. It is the authors’ engineering judgm ent that, given the

differences in test m e thods for m easuring 0-to-60 tim e and given the fact that the weight is based

on inertia weight, use of these other published values for the F and f coefficients would not result

in statistically significantly different 0-to-60 averages or trends. The results of a sim ilar

calculation of estim ated A top speed @ are also included in som e tables.

4

## Grouping all vehicles into classes and then constructing tim e trends of param eters of interest,

like m pg, can provide interesting and useful results. These results, however, are a strong

function of the class definitions. Classes based on other definitions than those used in this report

are possible, and results from these other classifications m ay also be useful.

For cars, vehicle classification as to vehicle type, size class, and m anufacturer/origin

generally follows fuel econom y label, Fuel Economy Guide , and fuel econom y standards

protocols; exceptions are listed in Table A-3, Appendix A. In m any of the passenger car tables,

large sedans and wagons are aggregated as "Large," m i dsize sedans and wagons are aggregated

as "Midsize," and "Sm all" includes all other cars. In som e of the car tables, an alternative

classification system is used, nam ely: Large Cars, Large W agons, Midsize Cars, Midsize

W a gons, Sm all Cars, and Sm all W a gons with the EPA Two-Seater, Mini-Com pact, Subcom pact,

and Com p act car classes are com b ined into the A Sm all Car @ class. In som e of the tables and

figures in this report, only four vehicle types are used. In these cases, wagons have been m erged

with cars. This is because the wagon sales fraction for som e instances is so sm all that the

inform ation is m o re conveniently represented by com b ining the two vehicle types. W h en they

have been com b ined, the differences between them are not im portant.

The truck classification schem e used for all m odel years in this report is slightly different

from that used in som e previous reports in this series, because pickups, vans, and sports utility

vehicles (SUVs) are som etim es each subdivided as A Sm all, @ A Midsize, @ and A Large. @ These truck

size classifications are based prim arily on published wheelbase data according to the following

criteria:

Pickup Van SUV

Sm all Less than 105" Less than 109" Less than 100"

Midsize 105" to 115" 109" to 124" 100" to 110"

Large More than 115" More than 124" More than 110"

This classification schem e is sim ilar to that used in m any trade and consum er publications. For those vehicle nam eplates with a variety of wheelbases, the size classification

was determ ined by considering only the sm allest wheelbase produced. The classification of a

vehicle for this report is based on the authors’ engineering judgm ent and is not a replacem ent for

definitions used in im plem enting autom o tive standards legislation.

Published data is also used for two other vehicle characteristics for which data is not

currently being subm itted to EPA by the autom o tive m anuf acturers: (1) engines with variable

valve tim ing (VVT) that use either cam s or electric solenoids to provide variable intake and/ or

exhaust valve tim ing and in som e cases valve lift; and (2) engines with cylinder deactivation,

which involves allowing the valves of selected cylinders of the engine to rem ain closed under

certain driving conditions.

5

## III. General Car and Truck Trends

Figure 1 and Table 1 depict tim e trends in car , light truck, and car-plus-light truck fuel

econom y. Also shown on Figure 1 is the fraction of the com b ined fleet that are light trucks and

trend lines representing three-year m oving averag es of the fuel econom y and truck sales fraction

data. Since 1975, the fuel econom y of the com b ined car and light truck fleet has m oved

through several phases:

1. a rapid increase from 1975 through the early1980s,

2. a slow increase until reaching its peak in 1987,

3. a gradual decline until 2004, and

4. an increase in 2005 and 2006, with 2007 levels projected to be sim ilar to 2006.

A d j u sted Fu el Eco n o m y an d Percen t Tru ck by Mo de l Year

(Th r ee Year Mo v i ng A v erage)

10 0%

Mov i ng A v g.

Y e arly D a t a 

### 75 %

Cars

Both



### 50 % Truc ks

Pe rce n t Truc k



### 25 %

0%

1970 1975 1980 198 5 19 90 1995 2000 2005 2010

M o del Year

Fi gur e 1 10 15 20 25 30 Perce n t Tr uck

Ca r s

T r ucks

Pct. Tru c k Bo th A d justed C o mp osite M P G



## 6

## As shown in Table 1, the MY2006 and projected MY2007 fleetwide fuel econom y value

of 20.2 m pg is the highest value since 1996 and is 0.9 m pg higher than the 2004 value of 19.3

m pg, which was the lowest value since 1980. The back-to-back annual increases in 2005 and

2006 are the first such increases since the m i d-1980s. These increases reverse the longer term

trend of declining fuel econom y since its peak in 1987. Most of the increase in overall fuel

econom y since 2004 is due to higher truck fuel econom y, as truck fuel econom y has increased by

1.0 m pg since 2004, while car fuel econom y has increased by 0.3 m pg. The 20.2 m pg adjusted

fuel econom y value for 2006-2007 is 1.8 m pg below the peak in 1987, but m uch of this difference

is due to the new m e thodology for calculating adjusted fuel econom y values that is phased in over

the 1986-2005 tim efram e

. As shown in Table 1, based on laboratory 55/45 fuel econom y values,

the 2006-2007 value of 25.3 m pg is 0.6 m pg lower than the peak of 25.9 m pg in 1987.

Figure 1 shows that the estim ated light truck share of the m arket, based on the three-year

m oving average trend, has leveled off at about 50 percent. Figure 2 com p ares laboratory 55/45

fuel econom y for the com b ined car and truck fleet and the sales fraction for trucks.

MY2007 cars are estim ated to average 23.4 m pg and are near the high end of their m pg

range since 1996. For MY2007, light trucks are estim ated to average 17.7 m pg, their highest

level since 1991. Fuel econom y standards were unchanged for MY1996 through MY2004. In

2003 DOT raised the truck CAFE standards for 2005-2007, and in 2006 DOT raised the truck

CAFE standards for 2008-2011.. The recent fuel econom y im provem e nt for trucks is likely due,

in part, to these higher standards. The CAFE standard for cars has not been changed since 1990.



# Truck Sales Fraction v s Fleet MP G by Model Year

La b. 5 5/ 45 M P G

10% 2 0% 30% 4 0% 50 % 6 0% 70 %

Per c ent Tr uck

Fi gur e 2 10 15 20 25 30

1990 1995 2000 2007

2004 19 85

1975 19 80



## 7

### Table 1

**Fuel Economy Characteristics of 1975 to 2007 Light Duty Vehicles**

**Cars**

**MODEL SALES**  **<---- FUEL ECONOMY ----> TON**  **CU-FT CU-FT** 

**YEAR (000)**  **FRAC LAB**  **ADJ ADJ**  **ADJ -MPG**  **-MPG TON-MPG** 

**55/45 CITY**  **HWY COMP** 

1975 8237 .806 15.8 12.3 15.2 13.5 27.6

1976 9722 .788 17.5 13.7 16.6 14.9 30.2

1977 11300 .800 18.3 14.4 17.4 15.6 31.0 1780 3423

1978 11175 .773 19.9 15.5 19.1 16.9 30.6 1908 3345

1979 10794 .778 20.3 15.9 19.2 17.2 30.2 1922 3301

1980 9443 .835 23.5 18.3 22.6 20.0 31.2 2136 3273

1981 8733 .827 25.1 19.6 24.2 21.4 33.1 2338 3547

1982 7819 .803 26.0 20.1 25.5 22.2 34.2 2419 3645

1983 8002 .777 25.9 19.9 25.5 22.1 34.7 2476 3776

1984 10675 .761 26.3 20.2 26.0 22.4 35.1 2482 3776

1985 10791 .746 27.0 20.7 26.8 23.0 35.8 2553 3884

1986 11015 .717 27.9 21.2 27.6 23.7 36.2 2598 3899

1987 10731 .722 28.1 21.2 27.7 23.8 36.2 2584 3872

1988 10736 .702 28.6 21.4 28.2 24.1 36.9 2631 3963

1989 10018 .693 28.1 20.9 27.9 23.7 36.8 2591 3977

1990 8810 .698 27.8 20.5 27.5 23.3 37.1 2528 3984

1991 8524 .678 28.0 20.5 27.6 23.4 37.0 2540 3970

1992 8108 .666 27.6 20.0 27.5 23.1 37.4 2534 4071

1993 8456 .640 28.2 20.3 27.9 23.5 37.7 2580 4098

1994 8415 .596 28.0 20.0 27.7 23.3 37.9 2554 4108

1995 9396 .620 28.3 20.0 28.1 23.4 38.3 2584 4171

1996 7890 .600 28.3 19.8 28.0 23.3 38.3 2572 4186

1997 8335 .576 28.4 19.8 28.0 23.4 38.3 2565 4168

1998 7972 .551 28.5 19.7 28.0 23.4 38.7 2565 4210

1999 8379 .551 28.2 19.4 27.5 23.0 38.7 2531 4237

2000 9128 .551 28.2 19.3 27.3 22.9 38.6 2534 4246

2001 8408 .539 28.4 19.4 27.3 23.0 39.1 2551 4280

2002 8304 .515 28.6 19.4 27.2 23.1 39.3 2561 4311

2003 7951 .504 28.9 19.5 27.5 23.2 40.0 2582 4378

2004 7538 .480 28.9 19.3 27.4 23.1 40.3 2601 4464

2005 8025 .505 29.5 19.6 27.6 23.5 41.0 2677 4590

2006 8109 .539 29.2 19.4 27.5 23.3 41.5 2660 4646

2007 7580 .510 29.4 19.5 27.6 23.4 42.6 2689 4762



## 8

### Table 1 (continued)

**Fuel Economy Characteristics of 1975 to 2007 Light Duty Vehicles**

**Trucks**

**MODEL SALES**  **<---- FUEL ECONOMY ----> TON** 

**YEAR (000)**  **FRAC LAB**  **ADJ ADJ**  **ADJ**

**55/45 CITY**  **HWY COMP**  **-MPG**

1975 1987 .194 13.7 10.9 12.7 11.6 24.2

1976 2612 .212 14.4 11.5 13.2 12.2 26.0

1977 2823 .200 15.6 12.6 14.1 13.3 28.0

1978 3273 .227 15.2 12.4 13.7 12.9 27.5

1979 3088 .222 14.7 12.1 13.1 12.5 27.3

1980 1863 .165 18.6 14.8 17.1 15.8 30.9

1981 1821 .173 20.1 16.0 18.6 17.1 33.0

1982 1914 .197 20.5 16.3 19.0 17.4 33.7

1983 2300 .223 20.9 16.5 19.6 17.8 34.0

1984 3345 .239 20.5 16.1 19.3 17.4 33.5

1985 3669 .254 20.6 16.2 19.4 17.5 33.7

1986 4350 .283 21.4 16.8 20.2 18.2 34.3

1987 4134 .278 21.6 16.8 20.5 18.3 34.2

1988 4559 .298 21.2 16.2 20.2 17.9 34.5

1989 4435 .307 20.9 15.9 19.8 17.6 34.7

1990 3805 .302 20.7 15.6 19.8 17.4 35.1

1991 4049 .322 21.3 15.9 20.3 17.8 35.3

1992 4064 .334 20.8 15.5 19.9 17.4 35.4

1993 4754 .360 21.0 15.5 20.1 17.5 35.7

1994 5710 .404 20.8 15.3 19.7 17.2 35.7

1995 5749 .380 20.5 15.0 19.5 17.0 35.7

1996 5254 .400 20.8 15.1 19.9 17.2 36.6

1997 6124 .424 20.6 14.8 19.5 17.0 36.9

1998 6485 .449 20.9 14.9 19.8 17.1 36.8

1999 6839 .449 20.5 14.6 19.2 16.7 37.0

2000 7447 .449 20.8 14.7 19.4 16.9 37.1

2001 7202 .461 20.6 14.6 19.1 16.7 37.4

2002 7815 .485 20.6 14.4 19.1 16.7 38.0

2003 7824 .496 20.9 14.6 19.3 16.9 38.7

2004 8173 .520 20.8 14.3 19.2 16.7 39.4

2005 7866 .495 21.4 14.6 19.8 17.2 40.2

2006 6932 .461 21.9 15.0 20.2 17.6 40.8

2007 7290 .490 22.1 15.1 20.4 17.7 42.0



## 9

### Table 1 (continued)

**Fuel Economy Characteristics of 1975 to 2007 Light Duty Vehicles**

**Cars and Trucks**

**MODEL SALES**  **<---- FUEL ECONOMY ----> TON** 

**YEAR (000)**  **FRAC LAB**  **ADJ ADJ**  **ADJ**

**55/45 CITY**  **HWY COMP**  **-MPG**

1975 10224 1.000 15.3 12.0 14.6 13.1 26.9

1976 12334 1.000 16.7 13.2 15.7 14.2 29.3

1977 14123 1.000 17.7 14.0 16.6 15.1 30.4

1978 14448 1.000 18.6 14.7 17.5 15.8 29.9

1979 13882 1.000 18.7 14.9 17.4 15.9 29.5

1980 11306 1.000 22.5 17.6 21.5 19.2 31.2

1981 10554 1.000 24.1 18.8 23.0 20.5 33.1

1982 9732 1.000 24.7 19.2 23.9 21.1 34.1

1983 10302 1.000 24.6 19.0 23.9 21.0 34.5

1984 14020 1.000 24.6 19.1 24.0 21.0 34.7

1985 14460 1.000 25.0 19.3 24.4 21.3 35.3

1986 15365 1.000 25.7 19.8 25.0 21.8 35.7

1987 14865 1.000 25.9 19.8 25.3 22.0 35.7

1988 15295 1.000 25.9 19.6 25.2 21.9 36.2

1989 14453 1.000 25.4 19.1 24.8 21.4 36.2

1990 12615 1.000 25.2 18.7 24.6 21.2 36.5

1991 12573 1.000 25.4 18.8 24.7 21.2 36.5

1992 12172 1.000 24.9 18.2 24.4 20.8 36.8

1993 13211 1.000 25.1 18.2 24.4 20.9 37.0

1994 14125 1.000 24.6 17.8 23.8 20.4 37.0

1995 15145 1.000 24.7 17.7 24.1 20.5 37.3

1996 13144 1.000 24.8 17.6 24.0 20.4 37.6

1997 14459 1.000 24.5 17.4 23.6 20.1 37.7

1998 14458 1.000 24.5 17.2 23.6 20.1 37.9

1999 15218 1.000 24.1 16.9 23.0 19.7 38.0

2000 16574 1.000 24.3 16.9 23.0 19.8 37.9

2001 15610 1.000 24.2 16.8 22.8 19.6 38.3

2002 16119 1.000 24.1 16.6 22.5 19.4 38.7

2003 15775 1.000 24.3 16.7 22.7 19.6 39.4

2004 15711 1.000 24.0 16.3 22.4 19.3 39.9

2005 15890 1.000 24.8 16.8 23.1 19.9 40.6

2006 15041 1.000 25.3 17.1 23.5 20.2 41.2

2007 14871 1.000 25.3 17.1 23.6 20.2 42.3



## 10

## The distribution of fuel econom y in any m odel y ear is of interest. In Figure 3, highlights

of the distribution of car m pg are shown. Sin ce 1975, half of the cars have consistently been

within a few m pg of each other. The fuel econom y difference between the least efficient and

m o st efficient car increased from about 20 m pg in 1975 to nearly 50 m pg in 1986, but was less

than 35 m pg in 1999. W ith the introduction for sale of the Honda Insight gasoline-electric

hybrid vehicle in MY2000, the range once again approached 50 m pg. The increased m arket

share of hybrid cars also accounts for the increase in the fuel econom y of the best 1% of cars

with the cutpoint for this strata now over 40 m pg. The ratio of the highest to lowest has

increased from about three to one in 1975 to nearly five to one today, because the fuel econom y

of the least fuel efficient cars has rem ained roughly constant in com p arison to the m o st fuel

efficient cars whose fuel econom y has m o re than doubled.

The overall fuel econom y distribution trend for trucks (see Figure 4) is narrower than that

for cars, with a peak in the efficiency of the m o st efficient truck in the early 1980s when sm all

pickup trucks equipped with diesel engines were being sold. As a result, the fuel econom y range

between the m o st efficient and least efficient truck peaked at about 25 m pg in 1982. The fuel

econom y range for trucks then narrowed, but with the introduction of the hybrid Escape SUV in

MY2005, it is nearly 20 m pg. Like cars, half of the trucks built each year have always been

within a few m pg of each year = s average fuel econom y value. Appendix C contains additional

fuel econom y distribution data.

S al es W ei g h t ed C ar

Fu e l E c ono m y D i s t r i but i on

A d j u st ed C o m p o s i t e MP G

70

60

50 

### Sa l e s W e i g ht e d Tr uc k

Fu e l Ec on om y D i s t r i b u t i o n

A d j u st ed C o m p osi t e M P G

70

60

50

1975 1980 19 85 1990 1995 2000 20 05

M ode l Y e a r B est

Ca r

Wor s t

Ca r 50% o f C ar s Fi r s t Hy br i d

Ca r

Be s t 1 %

40 40

30 30

19 75 19 80 1 985 1 990 1 995 2000 2005

M ode l Y e a r B est

Tr uc k

Wo r s t

Tr uc k 5 0 % of Tr uc k s B est 1%

20 20

Wo r s t 1 %

Wo r s t 1 %

10 10

0 0

Fi g u r e 3

Fi g ur e 4



## 11

### Table 2

**Vehicle Size and Design Characteristics of 1975 to 2007**

**Cars**

**<------ Vehicle Characteristics: -----------> <- Percent By: ->** 

**MODEL ADJ**  **VOL WGHT**  **ENG HP/ 0-60 TOP**  **VEHICLE SIZE**

**YEAR FRAC**  **COMP CU-FT**  **LB HP**  **WT TIME SPD**  **SMALL MID**  **LARGE**

**MPG**

1975 .806 13.5 4058 136 .0331 14.2 111 55.4 23.3 21.3

1976 .788 14.9 4059 134 .0324 14.4 110 55.4 25.2 19.4

1977 .800 15.6 110 3944 133 .0335 14.0 111 51.9 24.5 23.5

1978 .773 16.9 109 3588 124 .0342 13.7 111 44.7 34.4 21.0

1979 .778 17.2 109 3485 119 .0338 13.8 110 43.7 34.2 22.1

1980 .835 20.0 104 3101 100 .0322 14.3 107 54.4 34.4 11.3

1981 .827 21.4 106 3076 99 .0320 14.4 106 51.5 36.4 12.2

1982 .803 22.2 106 3054 99 .0320 14.4 106 56.5 31.0 12.5

1983 .777 22.1 109 3112 104 .0330 14.0 108 53.1 31.8 15.1

1984 .761 22.4 108 3099 106 .0339 13.8 109 57.4 29.4 13.2

1985 .746 23.0 108 3093 111 .0355 13.3 111 55.7 28.9 15.4

1986 .717 23.7 107 3041 111 .0360 13.2 111 59.5 27.9 12.6

1987 .722 23.8 107 3031 112 .0365 13.0 112 63.5 24.3 12.2

1988 .702 24.1 107 3047 116 .0375 12.8 113 64.8 22.3 12.8

1989 .693 23.7 108 3099 121 .0387 12.5 115 58.3 28.2 13.5

1990 .698 23.3 107 3176 129 .0401 12.1 117 58.6 28.7 12.8

1991 .678 23.4 107 3154 132 .0413 11.8 118 61.5 26.2 12.3

1992 .666 23.1 108 3240 141 .0428 11.5 120 56.5 27.8 15.6

1993 .640 23.5 108 3207 138 .0425 11.6 120 57.2 29.5 13.3

1994 .596 23.3 108 3250 143 .0432 11.4 121 58.5 26.1 15.4

1995 .620 23.4 109 3263 152 .0460 10.9 125 57.3 28.6 14.0

1996 .600 23.3 109 3282 154 .0464 10.8 125 54.3 32.0 13.6

1997 .576 23.4 109 3274 156 .0469 10.7 126 55.1 30.6 14.3

1998 .551 23.4 109 3306 159 .0475 10.6 127 49.4 39.1 11.4

1999 .551 23.0 109 3365 164 .0481 10.5 128 47.7 39.7 12.6

2000 .551 22.9 110 3369 168 .0492 10.4 129 47.5 34.3 18.2

2001 .539 23.0 109 3380 168 .0492 10.3 129 50.9 32.3 16.8

2002 .515 23.1 109 3391 173 .0504 10.2 131 48.6 36.3 15.1

2003 .504 23.2 109 3421 176 .0510 10.0 132 50.8 33.4 15.9

2004 .480 23.1 110 3462 182 .0521 9.8 133 47.4 35.5 17.0

2005 .505 23.5 111 3463 182 .0519 9.8 133 44.2 38.9 16.9

2006 .539 23.3 112 3527 192 .0537 9.6 136 46.0 33.7 20.3

2007 .510 23.4 111 3588 200 .0548 9.5 138 42.2 38.3 19.5



## 12

### Table 2 (Continued)

**Vehicle Size and Design Characteristics of 1975 to 2007**

**Trucks**

**<-- Vehicle Characteristics: --------> <-- Percent By: -->** 

**MODEL SALES ADJ**  **WGHT ENG**  **HP/ 0-60 TOP VEHICLE TYPE** 

**YEAR FRAC**  **COMP LB**  **HP WT**  **TIME SPD VAN**  **SUV PICKUP** 

**MPG**

1975 .194 11.6 4072 142 .0349 13.6 114 23.0 9.4 67.6

1976 .212 12.2 4155 141 .0340 13.8 113 19.2 9.3 71.4

1977 .200 13.3 4135 147 .0356 13.3 115 18.2 10.0 71.8

1978 .227 12.9 4151 146 .0351 13.4 114 19.1 11.6 69.3

1979 .222 12.5 4252 138 .0325 14.3 111 15.6 13.0 71.5

1980 .165 15.8 3869 121 .0313 14.5 108 13.0 9.9 77.1

1981 .173 17.1 3806 119 .0311 14.6 108 13.5 7.5 79.1

1982 .197 17.4 3806 120 .0317 14.5 109 16.2 8.5 75.3

1983 .223 17.8 3763 118 .0313 14.5 108 16.6 12.6 70.8

1984 .239 17.4 3782 118 .0310 14.7 108 20.2 18.7 61.1

1985 .254 17.5 3795 124 .0326 14.1 110 23.3 20.0 56.6

1986 .283 18.2 3738 123 .0330 14.0 110 24.0 17.8 58.2

1987 .278 18.3 3713 131 .0351 13.3 113 26.9 21.1 51.9

1988 .298 17.9 3841 141 .0366 12.9 115 24.8 21.2 53.9

1989 .307 17.6 3921 146 .0372 12.8 116 28.8 20.9 50.3

1990 .302 17.4 4005 151 .0377 12.6 117 33.2 18.6 48.2

1991 .322 17.8 3948 150 .0379 12.6 117 25.5 27.0 47.4

1992 .334 17.4 4056 155 .0382 12.5 118 30.0 24.7 45.3

1993 .360 17.5 4073 162 .0398 12.1 120 30.3 27.6 42.1

1994 .404 17.2 4125 166 .0403 12.0 121 24.8 28.4 46.7

1995 .380 17.0 4184 168 .0401 12.0 121 28.9 31.6 39.5

1996 .400 17.2 4225 179 .0423 11.5 124 26.8 36.0 37.2

1997 .424 17.0 4344 187 .0429 11.4 126 20.7 40.0 39.3

1998 .449 17.1 4283 187 .0435 11.2 126 23.0 39.8 37.2

1999 .449 16.7 4412 197 .0446 11.0 128 21.4 41.4 37.2

2000 .449 16.9 4375 197 .0448 11.0 128 22.7 42.2 35.1

2001 .461 16.7 4463 209 .0466 10.6 131 17.1 47.9 35.0

2002 .485 16.7 4546 219 .0482 10.4 134 15.9 53.6 30.5

2003 .496 16.9 4586 221 .0481 10.4 134 15.7 52.6 31.6

2004 .520 16.7 4710 236 .0501 10.0 137 11.7 57.7 30.7

2005 .495 17.2 4668 237 .0505 10.0 137 18.8 51.9 29.2

2006 .461 17.6 4628 234 .0504 10.0 137 16.6 52.9 30.6

2007 .490 17.7 4723 247 .0521 9.7 140 13.1 59.0 27.9



## 13

### Table 2 (Continued)

**Vehicle Size and Design Characteristics of 1975 to 2007**

**Cars and Trucks**

**<--- Vehicle Characteristics: -------->**

**MODEL SALES ADJ**  **WGHT ENG**  **HP/ 0-60 TOP**

**YEAR FRAC**  **COMP LB**  **HP WT**  **TIME SPD**

**MPG**

1975 1.000 13.1 4060 137 .0335 14.1 112

1976 1.000 14.2 4079 135 .0328 14.3 111

1977 1.000 15.1 3982 136 .0339 13.8 112

1978 1.000 15.8 3715 129 .0344 13.6 112

1979 1.000 15.9 3655 124 .0335 13.9 110

1980 1.000 19.2 3228 104 .0320 14.3 107

1981 1.000 20.5 3202 102 .0318 14.4 107

1982 1.000 21.1 3202 103 .0320 14.4 107

1983 1.000 21.0 3257 107 .0327 14.1 108

1984 1.000 21.0 3262 109 .0332 14.0 109

1985 1.000 21.3 3271 114 .0347 13.5 110

1986 1.000 21.8 3238 114 .0351 13.4 111

1987 1.000 22.0 3221 118 .0361 13.1 112

1988 1.000 21.9 3283 123 .0372 12.8 114

1989 1.000 21.4 3351 129 .0382 12.5 115

1990 1.000 21.2 3426 135 .0394 12.2 117

1991 1.000 21.2 3410 138 .0402 12.1 118

1992 1.000 20.8 3512 145 .0413 11.8 120

1993 1.000 20.9 3519 147 .0416 11.8 120

1994 1.000 20.4 3603 152 .0420 11.7 121

1995 1.000 20.5 3613 158 .0438 11.3 123

1996 1.000 20.4 3659 164 .0447 11.1 125

1997 1.000 20.1 3727 169 .0452 11.0 126

1998 1.000 20.1 3744 171 .0457 10.9 126

1999 1.000 19.7 3835 179 .0465 10.7 128

2000 1.000 19.8 3821 181 .0472 10.6 129

2001 1.000 19.6 3879 187 .0480 10.5 130

2002 1.000 19.4 3951 195 .0493 10.3 132

2003 1.000 19.6 3999 199 .0496 10.2 133

2004 1.000 19.3 4111 211 .0511 9.9 135

2005 1.000 19.9 4060 209 .0512 9.9 135

2006 1.000 20.2 4034 212 .0522 9.8 136

2007 1.000 20.2 4144 223 .0534 9.6 139



## 14

# Ton-MPG by Model Year

(Three Y ear Mov i ng Av erage)

T on-M PG

20 25 30 35 40 45 50

C ars



### Trucks

197 0 1 975 198 0 19 85 199 0 199 5 20 00 200 5 20 10

M o de l Y ear

Figure 5



## As shown in Table 2, the average weight of the overall fleet declined slightly in both

MY2005 and MY2006, with a slight increase in car weight m o re than offset by a larger decrease

in truck weight. Overall average horsepower and 0-60 acceleration tim e were basically

unchanged in MY2005-2006. Average weight and perform a nce are projected to increase in

MY2007, and the projected levels would be the highest for the 1975-2007 tim efram e

. The

projected 2007 weight has increased by over 900 pounds and the average horsepower level has

m o re than doubled since the early 1980s.

The long term trends for both weight and perform a nce have been steady increases. As

shown in Figure 5, since 1975 Ton-MPG for both cars and trucks increased substantially; i.e.

over 60% for cars and 80% for trucks. Typicall y, Ton-MPG for both vehicle types has increased

at a rate of about one or two percent a year.

Another dram atic trend over that tim e fram e has been the substantial increase in

perform ance of cars and light trucks as m easured by their estim ated 0-to-60 tim e. These trends

are shown graphically in Figure 6 (for cars) and Fi gure 7 (for light trucks) which are plots of fuel

econom y versus perform a nce, with m odel years as indicated. Both graphs show the sam e story:

in the late 1970s and early 1980s, responding to the regulatory requirem ents for m pg

im provem ent, the industry increased m pg and kept perform ance roughly constant. After the

regulatory m pg requirem ents stabilized, m pg im provem ents slowed and perform ance

dram atically im proved. This trend toward increased perform ance is as im portant as the truck

m arket share trend in understanding trends in overall fleet m pg. Figures 8 and 9 are sim ilar to

Figures 6 and 7, but show the trends in weight and laboratory fuel econom y and show that the

era of weight reductions that took place for both cars and trucks between 1975 and the early

1980s has been followed by an era of weight increases until 2005.

15

# Car 55/45 Laboratory MPG v s 0 to 60 Time

by Model Year

55 /4 5 L ab

. M P G

9 1 0 1 1 1 2 1 3 1 4 1 5

0 to 6 0 Ti me (Sec .)

Fi gur e 6



# Truck 55/45 Laboratory MPG v s 0 to 60 Tim e

by Model Year

55/ 4 5 Lab. M P G

9 1 0 1 1 1 2 1 3 1 4 1 5

0 to 60 Ti me ( S ec. )

Fi gur e 7 15 20 25 30

2000 2007

1975 1985 1980 1989 1995



### 10 15 20 25

2000 2007 1995

1990

19 75 1979 1980 1985 1987



## 16

# Car 55/45 Laboratory MP G v s Inertia Weight

by Model Year

55 /4 5 L ab

. M P G

25 00 3 000 350 0 400 0 45 00

I ner t i a We ight

Fi gur e 8



# Truck 55/45 Laboratory MP G v s Inertia Weight

by Model Year 15 20 25 30

2000 1985 1988 2007

1980

1979 1977

1975



### 10 15 20 25 55/ 45 Lab. M P G

2000 1985 1987

2007

1995 1990

1975 1980



### 35 00 400 0 45 00 500 0

I n e r ti a Wei ght

Fi gur e 9



## 17

## IV. Trends by Vehicle Type, Siz e

, and Weight

Table 1 showed that for the past several years trucks have accounted for about 50 percent

of the light-duty vehicles produced each year. MY2004 was the peak year for trucks with 52

percent m arket share, and trucks have been between 46 and 50 percent since. Considering the

five classes: cars, wagons, sports utility vehi cles (SUVs), vans, and pickups, since 1975 the

biggest overall increase in m arket share has been for SUVs, up from less than two percent in 1975

to 29 percent this year (see Figure 10 and Table 3). The biggest overall decrease has been for

cars, down from over 70 percent of the fleet in 1975 to about 50 percent. By com p arison the sales

fraction for pickup trucks has rem ained constant at about 15 percent of the m arket.

Figures 11 to 15 com p are sales fractions by ve hicle type and size with the fleet again

stratified into five vehicle types: cars (i.e., c oupes, sedans, and hatchbacks), station wagons, vans,

SUVs, and pickup trucks; and three vehicle sizes: sm all, m i dsize, and large. As shown in Figure

15, large cars accounted for about 20 percent of all car sales in the late 1970s, but their share of

the car m arket dropped in the early 1980s to about 12 percent of the m arket where it rem ained for

about two decades, but has since increased. W ithin the car segm ent, the m arket share for sm all

cars peaked in the late 1980s at about 65 percent and is now lower than at anytim e since 1975.

Sa l e s F r a c t i o n by Ve hi c l e T y p e

( T h r ee Y e ar M o vi n g A ver ag e)

S al es F r act i o n 100%

1 9 7 6 198 0 1984 198 8 1 992 1996 2 000 2004

M o d el Y ear SU V

80%

60%

Ca r

40%

Wa g o n

20% Va n

P i cku p

0%

Fi g u r e 1 0



## 18

## Large wagons accounted for m o re than 20 percent of the wagon segm ent of the m a rket in

the late 1970s but then lost m arket share relatively consistently and were not produced at all

between 1996 and 2004 when they reem erged. They now account for about 15 percent of all

wagons, but less than one percent of all light vehicles. Sim ilarly (see Figure 13), large vehicles

accounted for nearly 40 percent of all vans through the early 1980s com p ared to less than 10

percent the past five years. Sm all vans have never had a significant m arket share, and none have

been produced in recent years. Figures 14 and 15 show that there have been an overall and

significant trend towards increased m arket share for both large SUVs and pickups, but there has

been a recent decrease in large SUV sales fraction.

Table 3 com p ares the sales fractions by vehicle type and size on a different basis, that for

the total m arket. Since 1975, the largest increases in sales fractions have been for m i dsize and

large SUVs. These two classes are expected to account for over 25 percent of all light vehicles

built this year, com p ared to com b ined totals of about 1.3 and 4.5 percent in 1975 and 1988,

respectively. Conversely, the largest sales fraction decrease has occurred for sm all cars which

accounted for 40 percent of all light-duty vehicles produced in 1975 and over 43 percent in 1988,

but less than 20 percent this year. For MY2007, it is projected that the m arket share for m i dsize

cars will exceed that for sm all cars. An overall decrease has occurred for large cars which

accounted for about 15 percent of total light-duty sales in 1975 when they ranked third. Between

then and 1988, their sales fraction dropped to less than 10 percent of the total m arket.

C ar S al es F r ac t i o n b y V eh i cl e S i z e W ag o n S al es Fr act i o n by V e h i cl e S i z e



### ( T h r ee Y e ar M o v i n g A v er a g e) ( T h r e e Y e ar M o vi n g A ve r ag e )

S al e s F r ac t i o n S al es F ract i o n

Sm a l l

Mi d s i z e

La r ge

1 97 6 1 98 0 1 98 4 19 88 1 992 1 996 200 0 2 00 4 197 6 198 0 1984 1 988 1 992 1 996 200 0 200 4

Mo d e l Y e a r Mo d e l Y e a r

Fi g u r e 1 1 Fi g u r e 1 2 0% 20 % 40 % 60 % 80 % 100%

La r ge Mi d s i z e Sm a l l

0% 20 % 40 % 60 % 80 % 10 0%



## 19

### Va n Sa l e s F r a c t i o n b y Ve h i c l e Si z e

( T h r ee Y ear M o vi ng A v e r ag e)

S al es F r a ct i o n 100%

80%

60%

40%

20%

0% La r g e M i ds iz e Sm a l l 

### S U V S al es Fr ac t i o n b y V e h i c l e S i z e

( T hr ee Y e a r M o vi ng A ver ag e )

Sa l e s F r a c t i o n 100 %

80 %

60 %

40 %

20 %

0% La r g e M id s iz e Sm a l l

197 6 1980 1984 1988 1 992 19 96 2 0 0 0 2004 197 6 1 980 19 84 1 988 1 992 19 96 2000 20 04

M o d e l Y ear M ode l Y e a r

F i gur e 1 3 Fi g u r e 1 4



### P i ck u p S al e s F r act i o n b y V ehi cl e S i z e

( T h r e e Y ear M o vi n g A v er ag e)

S al es F ract i o n 100 %

80%

60%

40%

20%

0%

1976 1980 198 4 198 8 1992 1996 2000 200 4 La r g e M id s iz e Sm a l l

M ode l Y e a r

Fi g u r e 1 5



## 20

### Table 3

**Sales Fractions of MY1975, MY1988 and MY2007**

**Light-Duty Vehicles by Vehicle Size and Type**

**Differences in Sales Fraction**

**Vehicle Sales Fraction**  **From 1975 From 1975**  **From 1988**

**Type Size**  **1975 1988**  **2007 To 2007**  **To 1988 To 2007** 

Car Small 40.0% 43.8% 17.2% -22.8% 3.9% -26.6%

Midsize 16.0% 13.8% 18.5% 2.5% -2.1% 4.7%

Large 15.2% 8.5% 9.3% -5.9% -6.7% .8%

All 71.1% 66.2% 45.1% -26.1% -5.0% -21.1%

Wagon Small 4.7% 1.7% 4.3% -0.4% -3.0% 2.6%

Midsize 2.8% 1.9% 1.0% -1.8% -1.0% -0.8%

Large 1.9% .5% .6% -1.3% -1.4% .1%

All 9.4% 4.0% 5.9% -3.5% -5.4% 1.9%

Van Small .0% .4% .0% .0% .3% -0.4%

Midsize 3.0% 6.2% 6.2% 3.3% 3.2% .1%

Large 1.5% .9% .2% -1.3% -0.6% -0.7%

All 4.5% 7.4% 6.4% 2.0% 2.9% -1.0%

SUV Small .5% 1.9% 1.2% .7% 1.4% -0.7%

Midsize 1.2% 4.0% 14.8% 13.6% 2.8% 10.8%

Large .1% .5% 13.0% 12.9% .3% 12.5%

All 1.8% 6.3% 28.9% 27.1% 4.5% 22.6%

Pickup Small 1.6% 2.2% .0% -1.6% .7% -2.2%

Midsize .5% 6.9% 1.9% 1.3% 6.3% -5.0%

Large 11.0% 7.0% 11.8% .8% -4.1% 4.8%

All 13.1% 16.1% 13.7% .5% 2.9% -2.4%

All Trucks 19.4% 29.8% 49.0% 29.6% 10.4% 19.2%



## 21

## Figures 16 through 20 show trends in perform a nce, weight, and adjusted fuel econom y for

cars, wagons, vans, SUVs, and pickups. For all fi ve vehicle types, there has been a clear long

term trend towards increased weight, m oderating since 2005 for wagons, vans, and SUVs.

Table 4 shows the lowest, average, and highest adjusted m pg perform ance by vehicle class and

size for three selected years. For both 1988 and 2007, the m pg perform ance is such that the

m i dsize vehicles in all classes have better fuel econom y than the corresponding entry for sm all

vehicles in 1975. In Table 5, the percentage changes obtainable from the entries in Table 4 are

presented. Average m pg for four classes (m idsize cars, large cars, m i dsize wagons and m i dsize

SUVs) have im proved over 80 percent since 1975. The average fuel econom y im provem e nts

between 1975 and 2007 for the truck classes range from 5 percent for m i dsize pickups to 91

percent for m i dsize SUVs. Since 1988, average fuel econom y has decreased for sm all cars, all

wagons, sm all SUVs, and m i dsize pickups and the largest im provem ents in average m pg has been

18 and 20 percent for m i dsize and large SUVs, respectively.

F ue l Econom y and Pe rf o r m a nce 

## Fue l Econom y and Pe rform a nce

( T h r ee Yea r M o v i n g A ver a g e ) 

## ( T h r ee Yea r M o vi n g A ver a g e)

Ca r s 

## Wag ons

M P G

, 0 t o 60 ( s ec. ) Ine r t ia

W

e ight (

lb s .) M P G

, 0 t o 60 ( sec

. ) Ine r t ia

W

e ight ( lbs

. )

W

e ight A

d j u st ed C o mp o si t e M P G

0 t o 60 T i m e 5000 35 5000 35

4500 30 4500 30

25 4000 25 4000

20 3500 20 3500

3000 15 3000 15

10 2500 10 2500

5 2000 5 2000

1 975 198 0 1985 1990 1 995 2000 2005 1975 198 0 1985 1990 1995 2000 2005

M ode l Y e a r M ode l Y e a r

Fi g u r e 1 6 F i g u r e 17 W

e ight A

d j u st ed C o mp o si t e M P G

0 t o 60 T i me



## 22

## Fue l Ec onom y and Pe rfo r m a nce

( T h r ee Ye a r M o vi n g A ve r a g e)

Va n s

35 M P G

, 0 t o 60 ( sec. ) Ine r t i a W e ight ( l bs .)

5000

30 4500

25 4000

20 3500

15 3000

10 2500

5 2000

1975 1 9 80 1985 1990 19 9 5 2000 2005

M ode l Y e a r We i g

h t

A

d j u st ed C o mp o s i t e M P G

0 t o 6 0 T i me 

## Fue l Econom y a nd Pe rform a nce

(Thre e Y e ar Mov i ng A v e r age )

SUV s

35 M P G

, 0 t o 60 ( se c

. ) Ine r t ia W e ig h t

(

lbs .)

50 0 0

30 45 0 0

25 40 0 0

20 35 0 0

15 30 0 0

10 25 0 0

5 20 0 0

1975 198 0 1985 1990 1995 2000 2005

M ode l Y e a r We i g

h t

A

d j u st ed C o m p o si t e M P G

0 t o 60 T i me

F i g u re 18 F i g u re 19



## Fue l Econom y and Pe rform a nc e

( T h r ee Yea r M o v i n g A ver a g e)

Pickups

M P G

, 0 t o 60 ( sec. ) Ine r t ia W e ight (

lbs .)

35 5000

30 4500

25 4000

20 3500

15 3000

10 2500

5 2000

1975 1980 1985 1990 1995 2000 2005

M o d el Y ear

F i g u re 20 W e ight

A

d j u st ed C o mp o si t e M P G

0 t o 60 T i me



## 23

## 24 Table 4

**Lowest, Average and Highest Adjusted Fuel Economy**

**by Vehicle Type and Size**

**Vehicle 1975 1988 2007**

**Type Size Low Avg. High Low Avg. High Low Avg. High**

Car Small 8.6 15.6 28.3 7.5 25.7 54.4 10.4 24.0 42.9

Midsize 8.6 11.6 18.4 10.5 22.6 27.7 12.0 24.5 46.2

Large 8.4 11.2 14.6 10.0 20.6 26.0 11.8 20.5 26.0

All 8.4 13.4 28.3 7.5 24.2 54.4 10.4 23.4 46.2

Wagon Small 11.8 19.1 24.1 17.1 26.3 33.2 16.2 25.9 31.3

Midsize 8.4 11.3 25.0 17.5 22.2 27.7 15.0 21.4 28.3

Large 8.4 10.2 12.8 19.2 19.4 19.4 12.7 18.1 22.4

All 8.4 13.8 25.0 17.1 23.3 33.2 12.7 24.0 31.3

Van Small 16.2 17.5 18.5 15.5 20.6 25.0

Midsize 8.2 11.3 18.4 11.3 18.4 23.4 17.9 19.9 23.0

Large 8.9 10.7 14.5 9.9 14.3 16.8 14.4 15.8 17.0

All 8.2 11.1 18.5 9.9 17.9 25.0 14.4 19.8 23.0

SUV Small 10.2 13.7 16.3 15.6 20.4 27.7 16.1 17.9 22.8

Midsize 8.2 10.2 18.4 10.2 16.5 23.6 12.7 19.5 29.7

Large 7.9 10.3 13.7 12.2 14.0 18.8 12.2 16.8 21.7

All 7.9 11.0 18.4 10.2 17.2 27.7 12.2 18.1 29.7

Pickup Small 13.0 19.2 20.8 13.3 21.0 24.6

Midsize 17.8 17.9 18.0 15.3 21.3 25.9 15.4 18.8 23.7

Large 7.6 11.1 18.5 9.8 15.2 21.0 12.2 15.8 21.2

All 7.6 11.9 20.8 9.8 18.1 25.9 12.2 16.2 23.7

All Cars 8.4 13.5 28.3 7.5 24.1 54.4 10.4 23.4 46.2

All Trucks 7.6 11.6 20.8 9.8 17.9 27.7 12.2 17.7 29.7

All Vehicles 7.6 13.1 28.3 7.5 21.9 54.4 10.4 20.2 46.2

### Table 5

**Percent Change in Lowest, Average and Highest Adjusted Fuel Economy**

**by Vehicle Type and Size**

**Vehicle From 1975 to 2007**  **From 1975 to 1988 From 1988 to 2007** 

**Type Size**  **Low Avg**  **High Low**  **Avg. High**  **Low Avg.**  **High**

Car Small 21% 54% 52% -12% 65% 92% 39% -6% -20%

Midsize 40% 111% 151% 22% 95% 51% 14% 8% 67%

Large 40% 83% 78% 19% 84% 78% 18% 0% 0%

All 24% 75% 63% -10% 81% 92% 39% -2% -14%

Wagon Small 37% 36% 30% 45% 38% 38% -4% -1% -5%

Midsize 79% 89% 13% 108% 96% 11% -13% -3% 2%

Large 51% 77% 75% 129% 90% 52% -33% -6% 15%

All 51% 74% 25% 104% 69% 33% -25% 3% -5%

Van Small -3% 18% 35%

Midsize 118% 76% 25% 38% 63% 27% 58% 8% -1%

Large 62% 48% 17% 11% 34% 16% 45% 10% 1%

All 76% 78% 24% 21% 61% 35% 45% 11% -7%

SUV Small 58% 31% 40% 53% 49% 70% 3% -11% -17%

Midsize 55% 91% 61% 24% 62% 28% 25% 18% 26%

Large 54% 63% 58% 54% 36% 37% 0% 20% 15%

All 54% 65% 61% 29% 56% 51% 20% 5% 7%

Pickup Small 2% 9% 18%

Midsize -12% 5% 32% -13% 19% 44% 1% -11% -7%

Large 61% 42% 15% 29% 37% 14% 24% 4% 1%

All 61% 36% 14% 29% 52% 25% 24% -9% -7%

All Cars 24% 73% 63% -10% 79% 92% 39% -2% -14%

All Trucks 61% 53% 43% 29% 54% 33% 24% 0% 7%

All Vehicles 37% 54% 63% 0% 67% 92% 39% -7% -14%



## 25

## Cars and light trucks with conventional driv etrains have a fuel consum ption and weight

relationship which is well known and is shown on Figures 21 and 22. Fuel consum ption

increases linearly with weight. Because vehicl es with different propulsion system s, i.e., diesels

and hybrids, occupy a different place on such a fuel consum ption and weight plot, the data for

hybrid and diesel vehicles are plotted separately and excluded from the regression lines shown

on the graphs. At constant weight, MY2007 cars consum e about 30 to 40 percent less fuel per

m ile than their MY1975 counterparts

On this sam e constant weight basis, this year = s cars with diesel engines nom inally

consum e about 30 percent less fuel than the conventionally powered ones, while this year = s

hybrid cars are about 50 percent better. Sim ilarly, at constant weight this year = s conventionally

powered trucks achieve about 40 percent better fuel consum ption than MY1975 vehicles did.

Figures 23 and 24 show that the relationship between interior volum e and fuel

consum ption is currently not as im portant as it used to be. The data points on both of these

graphs exclude two seaters and represent sales weighted average fuel consum ption calculated at

increm ents of 1.0 cu. ft. As was done for Figures 21 and 22, the data points for hybrid and diesel

vehicles were plotted separately from that for the conventionally powered vehicles.

Figures 25 and 26 show the im provem e nt that occurred between 1975 and 2007 for fuel

consum ption as a function of 0-to-60 tim e for cars and trucks. Figures 27 and 28 com p are TonMPG data versus 0-to-60 tim e and show that at constant vehicle perform ance, there has been

substantial im provem ent in Ton-m pg, particularly for hybrid and diesel vehicles.

26

# Laboratory 55/4 5 Fuel Consumption

vs In ert i a W e ig ht

MY1975 and MY2007 Cars

0 2 4 6 8 10 12 G a l / 10 0 m i l e s

2007

Hy b r i d s

D i esels

1975 

### 19 75

20 07

15 00 25 00 3 50 0 4 50 0 5 50 0 65 00 75 00



### Inerti a Weight



## Figur e 2 1



# L a boratory 55/ 45 Fuel Co nsum p t ion

v s Inert i a Weigh t

MY197 5 an d MY2 007 Trucks

0 2 4 6 8 10 12 G a l / 1 0 0 mile s

19 75

20 07

Di e s els

Hy bri ds



### 1975 20 07

1500 2 5 00 35 00 450 0 5 500 6500 7 5 00

I n ert i a W e i ght



## Fi g u r e 2 2



## 27

### 0 2 4 6 8 10 12

Hy br ids

D i esels

Con v e n tio na l 

# Laboratory 55/45 Fuel Consumption

v s Int e rior Volu me

MY 1978 Cars

12 G a l / 10 0 m ile s



### 10

8

6

4

2 D i esel s

Conv en t i ona l



### 0

60 80 100 120 140 160 180

In te rior Vo lum e 

## Fi gure 23



# Laboratory 55/45 Fuel Consumption

vs Int e rior Volume

MY 2007 Cars

G a l / 10 0 mil e s

60 8 0 100 12 0 140 1 60 18 0

In t e ri o r Vo lu m e 

## Fig ur e 2 4



## 28

### Table 6

**Adjusted Fuel Consumption (Gal./100 miles) by Vehicle Type and Size**

**Vehicle 1975**  **1988 2007** 

**Type Size**  **Low Avg.**  **High Low**  **Avg. High**  **Low Avg.**  **High**

Car Small 11.6 6.4 3.5 13.3 3.9 1.8 9.6 4.2 2.3

Midsize 11.6 8.6 5.4 9.5 4.4 3.6 8.3 4.1 2.2

Large 11.9 8.9 6.8 10.0 4.9 3.8 8.5 4.9 3.8

All 11.9 7.5 3.5 13.3 4.1 1.8 9.6 4.3 2.2

Wagon Small 8.5 5.2 4.1 5.8 3.8 3.0 6.2 3.9 3.2

Midsize 11.9 8.8 4.0 5.7 4.5 3.6 6.7 4.7 3.5

Large 11.9 9.8 7.8 5.2 5.2 5.2 7.9 5.5 4.5

All 11.9 7.2 4.0 5.8 4.3 3.0 7.9 4.2 3.2

Van Small 6.2 5.7 5.4 6.5 4.9 4.0

Midsize 12.2 8.8 5.4 8.8 5.4 4.3 5.6 5.0 4.3

Large 11.2 9.3 6.9 10.1 7.0 6.0 6.9 6.3 5.9

All 12.2 9.0 5.4 10.1 5.6 4.0 6.9 5.1 4.3

SUV Small 9.8 7.3 6.1 6.4 4.9 3.6 6.2 5.6 4.4

Midsize 12.2 9.8 5.4 9.8 6.1 4.2 7.9 5.1 3.4

Large 12.7 9.7 7.3 8.2 7.1 5.3 8.2 6.0 4.6

All 12.7 9.1 5.4 9.8 5.8 3.6 8.2 5.5 3.4

Pickup Small 7.7 5.2 4.8 7.5 4.8 4.1

Midsize 5.6 5.6 5.6 6.5 4.7 3.9 6.5 5.3 4.2

Large 13.2 9.0 5.4 10.2 6.6 4.8 8.2 6.3 4.7

All 13.2 8.4 4.8 10.2 5.5 3.9 8.2 6.2 4.2

All Cars 11.9 7.5 3.5 13.3 4.1 1.8 9.6 4.3 2.2

All Trucks 13.2 8.6 4.8 10.2 5.6 3.6 8.2 5.6 3.4

All Vehicles 13.2 7.6 3.5 13.3 4.6 1.8 9.6 5.0 2.2



## 29

### Table 7

**Percent Change* in Adjusted Fuel Consumption by Vehicle Type and Size**

**Vehicle From 1975 to 2007**  **From 1975 to 1988 From 1988 to 2007** 

**Type Size**  **Low Avg.**  **High Low**  **Avg. High.**  **Low Avg.**  **High**

Car Small 17% 34% 34% -15% 39% 49% 28% -8% -28%

Midsize 28% 52% 59% 18% 49% 33% 13% 7% 38%

Large 29% 45% 44% 16% 45% 44% 15% 0% 0%

All 19% 43% 37% -12% 45% 49% 28% -5% -22%

Wagon Small 27% 25% 22% 32% 27% 27% -7% -3% -7%

Midsize 44% 47% 13% 52% 49% 10% -18% -4% 3%

Large 34% 44% 42% 56% 47% 33% -52% -6% 13%

All 34% 42% 20% 51% 40% 25% -36% 2% -7%

Van Small

-- -- -- -5% 14% 26%

-- -- --

Midsize 54% 43% 20% 28% 39% 20% 36% 7% 0%

Large 38% 32% 14% 10% 25% 13% 32% 10% 2%

All 43% 43% 20% 17% 38% 26% 32% 9% -8%

SUV Small 37% 23% 28% 35% 33% 41% 3% -14% -22%

Midsize 35% 48% 37% 20% 38% 22% 19% 16% 19%

Large 35% 38% 37% 35% 27% 27% 0% 15% 13%

All 35% 40% 37% 23% 36% 33% 16% 5% 6%

Pickup Small

-- -- -- 3% 8% 15%

-- -- --

Midsize -16% 5% 25% -16% 16% 30% 0% -13% -8%

Large 38% 30% 13% 23% 27% 11% 20% 5% 2%

All 38% 26% 13% 23% 35% 19% 20% -13% -8%

All Cars 19% 42% 37% -12% 45% 49% 28% -5% -22%

All Trucks 38% 35% 29% 23% 35% 25% 20% 0% 6%

All Vehicles 27% 34% 37% -1% 39% 49% 28% -9% -22%

*Note: A Negative Change indicates that the fuel consumption has increased.



## 30

### 4 

## Laborat o ry 55/4 5 Fuel C ons umption

vs 0 t o 60 Time

MY1975 and MY2007 C a rs

G a l / 100 m ile s

12

19 75

10 20 07

197 5 Hy bri d s

8

D i e sels

6

4

2 007

2

0

4 6 8 10 12 14 16 18 20 22 2 4

0 to 60 T i me (S ec.)



## Figu re 2 5



# Laboratory 55/45 Fuel Consumption

v s 0 to 60 Tim e

MY 1975 and MY2007 Trucks

12

10

8

6

4

2

0 G a l / 1 0 0 m ile s

1 975

20 07



### 6 8 1975

2007

Hy b r id s

Di esel s



### 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4

0 t o 6 0 T i me (S ec .)



## Figu re 2 6



## 311 975

2 007

Hy b r i d s

Di ese l s

Po w e r

2007

1975 

### MY19 75 and MY200 7 Cars

T on- M P G

10 0

80

60

40

20

0

0 5 10 15 20 25



### F igur e 27 0 to 60 Ti me (S ec. )



# Ton-M P G v s 0 to 60 Tim e

M Y 1975 and M Y 2007 Trucks

To n-M P G 10 0

19 75

20 07 

### 80

Hyb r id s

D i e sels



### 60

200 7



### 40

20

19 75



### 0

0 5 10 15 2 0 25

0 to 60 Time (Sec.)



## Fi gu r e 2 8



## 32

## Figure 29 and Table 8 show som e of the changes in the distribution of inertia weight that

have occurred over the years for the light-duty fleet. In 1975, 13 percent of all light-duty

vehicles had inertia weights of less than 3000 lb com p ared to two percent in 2007. Since 1988,

m arket share for vehicles with weight of 5000 pounds or m o re has increased from three percent

to 21 percent.

25 % 30 % Sales F r ac tio n D i st r i b u t i o n o f Li gh t Veh i cl e I ner t i a Weig h t F o r T hr ee M o de l Y ears

19 75 198 8 2 007

20 %

15 %

10 %

5%

0%

600 0 55 00 500 0 45 00 4 000 350 0 30 00 2 750 250 0 2 250 200 0 17 50

In er ti a W e igh t



### Figure 29

**Table 8**

**Light Vehicle Sales Fraction**

**by Inertia Weight Class**

**for Three Model Years**

**Inertia <----**  **Model Year ---->**

**Weight 1975**  **1988 2007** 

<3000 13.4% 27.2% 2.1%

3000 8.7% 25.4% 12.3%

3500 10.6% 25.2% 20.6%

4000 20.6% 13.2% 25.8%

4500 21.3% 6.0% 18.0%

5000 16.7% 2.4% 8.9%

5500 8.7% .5% 5.6%

>5500 .0% .0% 6.8%

Avg Wt. 4060 3283 4144



## 33

## Figures 30 through 34 provide an indication of the m a rket share of different weight vehicles

within the different classes. Trends within classes are shown which underlie the increasing

weight shown by the fleet as a whole. In 1975, a bout 40 percent of the cars had an inertia weight

of 4500 lb or m o re com p ared to about 5 percent this year. For MY2007, three weight classes

(3000, 3500 and 4000 lbs) account for nearly 90 percent of all cars. Conversely, the m a rket

share of trucks in the inertia weight classes of 4500 lb or m o re have increased substantially, and

these vehicles currently account for over 70 percent of all trucks, com p ared to about 30 percent

in 1975. Figures 32, 33, and 34 provide additional details of the truck data presented in Figure

31 for vans, SUVs, and pickups respectively. Appendi xes D, E, and F contain a series of tables

describing light-duty vehicles at the vehicle size/type level of stratif ication in m o re detail;

Appendix G provides sim ilar data by vehicle t ype and inertia weight class.

C ar M ar k et S h a r e b y I n er t i a W ei g h t C l ass T r u ck M ar ket S h ar e b y I n er t i a W ei g h t C l as s



### ( T h r ee Y ear M o v i n g A ver ag e) ( T h r ee Y ear M o vi n g A ve r ag e)

100% M a r k et S h ar e ( % ) 100 % M arket S h are ( % )

75% 75 %

50% 50 %

25% 25 %

0% 0%

1976 1 980 1984 1988 19 92 1996 2000 2004

Mo d e l Y e a r

F i gur e 3 0 Fi g u r e 3 1 < 2 750

3 500

4000 30 00 2750

197 6 198 0 1 984 198 8 199 2 19 96 2 000 200 4

M o d el Y ear 350 0

< 3500

400 0

450 0

> 4500



## 34

### V an M ar ket S h ar e b y I n er t i a W e i g h t C l ass S U V M ar ket S h ar e b y I n er t i a W ei g h t C l ass 

### ( T hr ee Y ear M o vi n g A ver ag e) ( T h r ee Y e ar M o vi n g A ver ag e )

M arket S h are ( % ) M a rket S h are ( % )

5000

< 4500

M ode l Y e a r M o d el Y ear

F i g u re 32 F i g u re 33



### P i ck u p M ar ket S h ar e b y I n e r t i a W ei g h t C l a ss

( T h r ee Y e ar M o vi n g A ver ag e)

M arket S h are ( % )

1976 1980 1984 1988 1992 19 96 2000 2004

M ode l Y e a r

F i g u re 34 1976 1980 198 4 1988 199 2 1996 2000 2004 0% 5% 10% 15% 20% 25% 30%

< 3500 350 0

> 4000 4000

1976 1980 1984 1988 1992 1996 2000 2004 0% 5% 10% 15% 20% 25% 30%

0% 5% 10% 15% 20% 25% 30%

< 3 500

4000

> 4500 3500

4500



## 35

## V. Technology Trends

Table 9 repeats the sales fraction and adjusted com posite fuel econom y data from Tables

1 and 2 and adds three m easures of powertrain inform ation: engine displacem ent (CID),

horsepower (HP), and specific power (HP/CID). This table also includes sales fraction data

giving the percent of vehicles that: have front- (FW D ) or four-wheel drive (4wd); have m anual,

lockup, or continuously variable (CVT) transm issions; have port or throttle body fuel injection

(TBI) or are Diesels; are equipped with engines that have m o re than two valves per cylinder; use

variable valve tim ing (VVT); and use hybrid vehicle technology.

For the overall MY2007 fleet, FW D continues to account for about one-half of the

m arket and 4wd for about 30 percent. W ith transm issions, m anuals rem ain less than 10 percent

of the m a rket, while CVTs have grown to seven percent. Over 70 percent of the MY2007 fleet

have m u lti-valve engines, and nearly 60 percent use VVT, an all-tim e high. Hybrids are over

two percent of the fleet for the first tim e, while diesels represent just 0.1 percent of the MY2007

sales. Appendix K contains additional data on fuel m e tering and num ber of valves per cylinder.

Table 10 com p ares technology usage for MY2007 by vehicle type and size. As discussed

earlier, wheelbase is used in this report to distinguish whether a truck is sm all, m i d-size, or large,

and four EPA car classes (Two-Seater, Minico m p act, Com p act, and Subcom pact) have been

com b ined to form the sm all car class. For this table, the car classes are separated into cars and

station wagons, so that the table stratifies light-dut y vehicles into a total of 15 vehicle types and

sizes. Note that this table does not contain any data for sm all vans and sm all pickups, because

none have been produced for several years.

Front-wheel drive (FW D ) is used heavily in all of the car classes, in sm all wagons and in

m i dsize vans. By com p arison, none of this year = s pickups or large vans will have front-wheel

drive, and it is used less often in SUVs or large vans than in m i dsize wagons. Conversely, fourwheel drive (4W D ) is used heavily in SUVs and pickups. A large portion of the m i dsize and

large wagons also have 4W D, but very little use of it is m ade in vans and cars.

Manual transm issions are used prim arily in sm all vehicles and m i dsize pickups.

Sim ilarly, usage of engines with m o re than two valves per cylinder is m o re prevalent on sm all

and m i dsize vehicles than on larger ones.

Detailed tabulations of different t echnology types, including technology usage

percentages for other m odel years, can be found in the Appendixes.

36Table 9

**Powertrain Characteristics of 1975 to 2007 Cars (Percentage Basis)**

**MODEL SALES**  **ADJ ENGINE**  **HP/ DRIVETRAIN**  **TRANSMISSION FUEL METERING**  **Multi**

**YEAR FRAC**  **COMP CID**  **HP CID**  **Front 4wd Manual Lock**  **CVT Port**  **TBI Dsl**  **Valve VVT Hybrid** 

**MPG**

1975 .806 13.5 288 136 .515 6.5 19.9 5.1 .2

1976 .788 14.9 287 134 .502 5.8 17.1 3.2 .3

1977 .800 15.6 279 133 .516 6.8 16.8 4.2 .5

1978 .773 16.9 251 124 .538 9.6 20.2 6.7 5.1 .9

1979 .778 17.2 238 119 .545 11.9 .3 22.3 8.0 4.7 2.1

1980 .835 20.0 188 100 .583 29.7 .9 31.9 16.5 6.2 .7 4.4

1981 .827 21.4 182 99 .594 37.0 .7 30.4 33.3 6.1 2.6 5.9

1982 .803 22.2 175 99 .609 45.6 .8 29.7 51.4 7.2 9.8 4.7

1983 .777 22.1 182 104 .615 47.3 3.1 26.5 56.7 9.5 18.9 2.1

1984 .761 22.4 179 106 .637 53.7 1.0 24.1 58.3 15.0 24.4 1.7

1985 .746 23.0 177 111 .671 61.6 2.1 22.8 58.7 21.4 32.0 .9

1986 .717 23.7 167 111 .701 71.1 1.1 24.8 58.0 36.7 28.4 .3

1987 .722 23.8 162 112 .732 77.0 1.1 24.9 59.5 42.5 30.5 .3

1988 .702 24.1 160 116 .759 81.7 .8 24.3 66.1 53.7 30.0

1989 .693 23.7 163 121 .783 82.5 1.0 21.0 69.3 .1 62.4 27.8 .0

1990 .698 23.3 163 129 .829 84.6 1.0 19.6 72.9 .0 77.5 21.1 .0 .6

1991 .678 23.4 163 132 .851 83.2 1.4 20.5 73.5 .0 78.0 21.8 .1 2.4

1992 .666 23.1 170 141 .868 80.8 1.1 17.4 76.4 89.5 10.4 .1 4.6

1993 .640 23.5 166 138 .865 85.1 1.2 17.8 77.0 91.6 8.4 4.8

1994 .596 23.3 168 143 .884 84.4 .4 16.7 79.3 94.9 5.1 8.0

1995 .620 23.4 167 152 .945 82.0 1.2 16.3 81.9 98.8 1.2 .1 9.8

1996 .600 23.3 165 154 .958 86.5 1.5 14.8 83.6 .0 98.8 1.1 .1 11.7

1997 .576 23.4 164 156 .974 86.5 1.7 13.5 85.8 .1 99.1 .8 .1 58.6 11.3

1998 .551 23.4 164 159 .993 87.0 2.3 12.3 87.3 .1 99.7 .1 .2 61.4 18.4

1999 .551 23.0 166 164 1.009 87.2 2.2 10.9 88.4 .0 99.7 .1 .2 64.6 17.1

2000 .551 22.9 165 168 1.032 84.9 2.1 11.2 87.7 .0 99.7 .1 .2 65.1 23.4 .1

2001 .539 23.0 165 168 1.042 84.1 3.2 11.4 87.5 .2 99.7 .3 67.2 28.3 .0

2002 .515 23.1 166 173 1.066 84.9 3.8 11.2 88.1 .4 99.6 .4 69.9 33.9 .3

2003 .504 23.2 166 176 1.086 81.7 3.8 11.1 87.9 .9 99.6 .4 73.5 41.2 .6

2004 .480 23.1 168 182 1.106 80.8 5.4 10.2 88.2 1.4 99.7 .3 77.2 44.2 .9

2005 .505 23.5 166 182 1.116 79.7 5.8 9.3 88.0 2.6 99.6 .4 78.2 51.7 2.1

2006 .539 23.3 171 192 1.142 76.8 5.7 9.8 87.5 2.4 99.4 .6 80.5 61.1 1.5

2007 .510 23.4 176 200 1.157 75.4 7.6 11.5 77.0 10.3 99.9 .1 82.1 67.9 3.0



## 37Table 9 (continued)

**Powertrain Characteristics of 1975 to 2007 Trucks (Percentage Basis)**

**MODEL SALES**  **ADJ ENGINE**  **HP/ DRIVETRAIN**  **TRANSMISSION FUEL METERING**  **Multi**

**YEAR FRAC**  **COMP CID**  **HP CID**  **Front 4wd Manual Lock**  **CVT Port**  **TBI Dsl**  **Valve VVT Hybrid** 

**MPG**

1975 .194 11.6 311 142 .476 17.1 37.0 .1

1976 .212 12.2 319 141 .458 22.9 34.8 .1

1977 .200 13.3 318 147 .482 23.6 32.0 .1

1978 .227 12.9 314 146 .481 29.0 32.4 .1 .8

1979 .222 12.5 298 138 .486 18.0 35.2 2.1 .3 1.8

1980 .165 15.8 248 121 .528 1.4 25.0 53.0 24.6 1.7 3.5

1981 .173 17.1 247 119 .508 1.9 20.1 51.6 31.1 1.1 5.6

1982 .197 17.4 243 120 .524 1.7 20.0 45.7 33.2 .7 9.3

1983 .223 17.8 231 118 .543 1.4 25.8 45.9 36.1 .6 4.7

1984 .239 17.4 224 118 .557 4.9 31.0 42.1 35.1 1.9 .6 2.3

1985 .254 17.5 224 124 .586 7.1 30.6 37.1 42.2 8.7 3.5 1.1

1986 .283 18.2 211 123 .621 5.9 30.3 42.7 42.0 21.8 18.7 .7

1987 .278 18.3 210 131 .654 7.4 31.5 39.9 44.8 33.3 33.6 .3

1988 .298 17.9 227 141 .650 9.0 33.3 35.5 53.1 43.3 44.4 .2

1989 .307 17.6 234 146 .653 9.9 32.0 32.7 56.8 45.9 47.6 .2

1990 .302 17.4 237 151 .668 15.5 31.3 28.1 67.4 55.2 40.8 .2

1991 .322 17.8 228 150 .681 9.7 35.3 31.0 67.4 55.0 43.2 .1

1992 .334 17.4 234 155 .685 13.6 31.4 27.3 71.5 65.9 32.5 .1

1993 .360 17.5 235 162 .710 15.1 29.4 23.3 75.7 73.4 25.7

1994 .404 17.2 239 166 .717 13.1 36.9 23.5 75.1 77.2 22.5

1995 .380 17.0 244 168 .715 17.7 40.7 20.5 78.6 79.8 20.2

1996 .400 17.2 243 179 .757 20.1 37.1 15.6 83.5 99.9 .1

1997 .424 17.0 248 187 .775 13.9 43.2 14.6 85.0 100.0 .0

1998 .449 17.1 242 187 .795 18.7 42.0 13.4 86.0 100.0 .0

1999 .449 16.7 249 197 .814 17.4 44.6 9.1 90.5 100.0

2000 .449 16.9 242 197 .832 19.4 42.4 8.0 91.7 100.0 4.7

2001 .461 16.7 243 209 .882 18.5 43.8 6.3 93.4 100.0 9.3

2002 .485 16.7 244 219 .918 18.5 47.6 4.9 94.7 .0 100.0 16.2

2003 .496 16.9 243 221 .927 19.2 46.5 4.8 93.7 1.2 100.0 19.8

2004 .520 16.7 252 236 .953 17.2 52.3 3.7 95.0 1.0 100.0 48.4 33.3

2005 .495 17.2 245 237 .983 25.7 48.3 3.0 95.0 2.0 99.9 .1 52.8 39.8 .1

2006 .461 17.6 240 234 .990 25.5 47.5 3.1 93.2 3.5 99.9 .1 62.1 49.9 1.5

2007 .490 17.7 245 247 1.023 24.5 48.8 3.6 92.5 3.9 99.8 .2 58.3 50.0 1.4



## 38Table 9 (continued)

**Powertrain Characteristics of 1975 to 2007 Cars and Trucks (Percentage Basis)**

**MODEL SALES**  **ADJ ENGINE**  **HP/ DRIVETRAIN**  **TRANSMISSION FUEL METERING**  **Multi**

**YEAR FRAC**  **COMP CID**  **HP CID**  **Front 4wd Manual Lock**  **CVT Port**  **TBI Dsl**  **Valve VVT Hybrid** 

**MPG**

1975 1.000 13.1 293 137 .507 5.3 3.3 23.2 4.1 .2

1976 1.000 14.2 294 135 .493 4.6 4.8 20.9 2.5 .0 .2

1977 1.000 15.1 287 136 .510 5.5 4.7 19.8 3.4 .0 .4

1978 1.000 15.8 266 129 .525 7.4 6.6 23.0 5.2 3.9 .0 .9

1979 1.000 15.9 252 124 .532 9.2 4.3 25.1 6.7 3.7 .1 2.0

1980 1.000 19.2 198 104 .574 25.0 4.9 35.4 17.8 5.2 .8 4.3

1981 1.000 20.5 193 102 .580 31.0 4.0 34.1 33.0 5.1 2.4 5.9

1982 1.000 21.1 188 103 .593 37.0 4.6 32.8 47.8 5.8 8.0 5.6

1983 1.000 21.0 193 107 .599 37.0 8.1 30.8 52.1 7.3 14.8 2.7

1984 1.000 21.0 190 109 .618 42.1 8.2 28.4 52.8 11.9 18.7 1.8

1985 1.000 21.3 189 114 .650 47.8 9.3 26.5 54.5 18.2 24.8 .9

1986 1.000 21.8 180 114 .678 52.6 9.3 29.8 53.5 32.5 25.7 .4

1987 1.000 22.0 175 118 .710 57.7 9.6 29.1 55.4 39.9 31.4 .3

1988 1.000 21.9 180 123 .726 60.0 10.5 27.6 62.2 50.6 34.3 .1

1989 1.000 21.4 185 129 .743 60.2 10.5 24.6 65.5 0.1 57.3 33.9 .1

1990 1.000 21.2 185 135 .781 63.8 10.1 22.2 71.2 70.8 27.0 .1

1991 1.000 21.2 184 138 .796 59.6 12.3 23.9 71.6 70.6 28.7 .1

1992 1.000 20.8 191 145 .807 58.4 11.2 20.7 74.8 81.6 17.8 .1

1993 1.000 20.9 191 147 .809 59.9 11.3 19.8 76.5 85.0 14.6

1994 1.000 20.4 197 152 .816 55.6 15.2 19.5 77.6 87.7 12.1

1995 1.000 20.5 196 158 .857 57.6 16.2 17.9 80.7 91.6 8.4 .0

1996 1.000 20.4 197 164 .878 60.0 15.7 15.1 83.5 99.3 .7 .1

1997 1.000 20.1 199 169 .890 55.8 19.3 14.0 85.5 99.5 .5 .1 39.6

1998 1.000 20.1 199 171 .904 56.4 20.1 12.8 86.7 99.8 .1 .1 40.9

1999 1.000 19.7 203 179 .921 55.8 21.3 10.1 89.4 99.9 .1 .1 43.4

2000 1.000 19.8 200 181 .942 55.5 20.2 9.7 89.5 99.8 .0 .1 44.8 15.0

2001 1.000 19.6 201 187 .968 53.8 21.9 9.0 90.2 0.1 99.9 .1 49.0 19.6

2002 1.000 19.4 203 195 .994 52.7 25.0 8.1 91.3 0.2 99.8 .2 53.3 25.3

2003 1.000 19.6 204 199 1.007 50.7 25.0 8.0 90.8 1.1 99.8 .2 55.5 30.6

2004 1.000 19.3 212 211 1.026 47.7 29.8 6.8 91.8 1.1 99.9 .1 62.3 38.5 .5

2005 1.000 19.9 205 209 1.050 53.0 26.8 6.2 91.5 2.3 99.7 .3 65.6 45.8 1.1

2006 1.000 20.2 203 212 1.072 53.1 25.0 6.7 90.1 2.9 99.6 .4 72.0 56.0 1.5

2007 1.000 20.2 210 223 1.091 50.5 27.8 7.7 84.6 7.1 99.9 .1 70.4 59.1 2.2



## 39

### Table 10

**MY2007 Technology Usage by Vehicle Type and Size**

**(Percent of Vehicle Type/Size Strata)**

**Front Four** 

**Vehicle Size**  **Wheel Wheel**  **Manual Multi-**  **Variable**

**Type Drive**  **Drive Trans.**  **Valve Valve** 

Car Small 70% 7% 23% 91% 65%

Midsize 86% 5% 6% 90% 85%

Large 61% 7% 1% 41% 47%

All 75% 6% 11% 80% 69%

Wagon Small 94% 5% 16% 100% 70%

Midsize 31% 53% 8% 84% 30%

Large 57% 43% 0% 80% 15%

All 79% 18% 13% 95% 57%

Van Small

Midsize 95% 5% 0% 53% 48%

Large 0% 11% 0% 0% 0%

All 92% 5% 0% 51% 46%

SUV Small 0% 89% 26% 29% 2%

Midsize 30% 59% 3% 83% 61%

Large 12% 57% 0% 53% 48%

All 21% 60% 3% 67% 53%

Pickup Small

Midsize 0% 27% 27% 70% 77%

Large 0% 50% 4% 38% 77%

All 0% 47% 7% 43% 46%



## 40

## Figures 35 through 39 show trends in drive use for the five vehicle classes. Cars used to

be nearly all rear-wheel drive; from 1988 to 2004 they were over 80 percent front-wheel drive

with a sm all four-wheel (4W D ) drive fraction. In recent years, there has been an increase in the

use of rear wheel drive from less than 12 percent in 1998 to 17 percent this year, and a slight

increase in the use of four wheel drive in cars with use of this technology increasing from about

two percent in the late 1990s to eight percent this year. Only a sm all percentage of wagons still

have rear-wheel drive, but in recent years they have m ade substantial use of 4W D.

The trend towards increased use of front wheel drive for vans is very sim ilar to that for

cars, except it started a few years later and appears to be continuing. Over 90 percent of vans

currently use front-wheel drive, com p ared to essentially none before 1984. SUVs are m o stly

4W D; but a trend toward front-wheel drive SUVs started in MY2000. Pickups rem a in the

bastion of rear-wheel drive with the increasing am ount of 4W D the only other drive option.

Except for a brief period in the early 1980s, front-wheel drive has not been used in pickups.

F r o n t

, R ear a n d F o u r W h eel D r i ve U sag e Fr ont

, R e a r a nd Fou r W he e l D r i v e U s a ge

( T h r e e Y ear M o vi n g A ver ag e) ( T h r ee Y ear M o vi n g A v er ag e)

Ca r s W a gons

S al es F ract i o n S al es F r act i o n 100 % 100%

1976 1980 1984 1988 199 2 19 96 2000 2004

M ode l Y e a r F r ont 4w d Re a r

80% 80%

60% 60%

40% 40%

20% 20%

0% 0%

1976 1980 1984 1988 1992 1996 2000 2004

M ode l Y e a r F r ont 4w d R ear

F igur e 3 5 F i gur e 3 6



## 41

### Fr ont

, R e a r an d Four W he e l D r i v e U s a ge

( T h r ee Y e ar M o vi n g A v er ag e)

Va n s

S al es F ract i o n 100%

80%

60%

40%

20%

0%

1976 1980 1984 1988 1992 1996 2000 2004

M ode l Y e a r F r ont 4w d R ear

F i g u re 37



### F r o n t

, R ear an d F o u r W h eel D r i ve U sa g e

( T h r ee Y ear M o vi n g A v er ag e)

P i c k ups

Sa l e s F r a c ti o n 100%

80%

60%

40%

20%

0%

19 76 1980 198 4 1988 1992 19 96 20 00 2 004

M ode l Y e a r F r ont 4w d R ear

F ig u r e 3 9 

### Fr o nt

, R e a r and Four W he e l D r i v e U s a g e

( T h r ee Y ea r M o vi n g A ver ag e )

SUV s

S al es F r ac t i o n 10 0%

80%

60%

40%

20%

0%

1976 1980 1 9 84 1988 1992 1996 2000 20 04

M o d e l Y ear F r ont 4w d R ear

F i g u r e 38



## 42

# Laboratory 55/45 MP G v s 0 to 60 Time

MY 2007 Cars

La bor at or y 5 5 / 4 5

MP G

4 6 8 1 0 1 2 1 4

0 t o 60 T i m e ( S e c .) I: F ast er 0 t o 60

Hig h e r M PG I I: Slo w e r 0 to 6 0

Hig h e r M PG

I V : Slow e r 0 to 60

L o w e r M P G II I : F a ster 0 to 6 0

L o w e r M P G Hy b r id s 

### 70

Di esels

Fr ont

Rear 

### 60

50 4w d



### 40

30

20

10

0

Fi gur e 40



## Figures 40 and 41 and Tables 11 and 12 give, as an indication of how the different drive

types are currently used, plots of fuel econom y and perform a nce for cars and trucks. The data

points in these graphs represent sales-weighted averages calculated at estim ated 0-to-60 tim e

increm ents of 0.1 sec. The trend lines in these two figures reflect the fuel econom y/

perform a nce tradeoff for conventionally powered vehicles, on the average. By drawing a

vertical line at the average perform ance, and a horizontal line at the average m pg, the space in

each figure is divided into four areas of better/worse perform ance crossed with better/worse fuel

econom y

Table 11

**Distribution of MY2007 Car Sales**

**By technology, 0-to-60 time and Lab 55/45 MPG**

**0 to 60 time <9.5 Sec**  **>9.5 sec <9.5 sec**  **>9.5 sec**

**Lab 55/45 MPG >29.4 MPG**  **>29.4 MPG <29.4 MPG**  **<29.4 MPG**

**Vehicle** Quadrant Quadrant Quadrant Quadrant

**Technology** I II III IV

Front Drive 7% 62% 24% 7%

Rear Drive 1% 2% 78% 19%

4wd 0% 2% 54% 44%

Hybrids 3% 97% 0% 0%

Diesels 60% 0% 0% 40%

All Cars 6% 47% 35% 12%



## 43

# Laboratory 55/45 MP G v s 0 to 60 Time

MY2007 Trucks

La bor at or y 5 5 / 4 5

MP G

4 6 8 1 0 1 2 1 4

0 t o 60 T i m e ( S e c .) I: F ast er 0 t o 60

Hig h e r M PG I I : Slo w e r 0 to 60

Hig h e r M PG

I V : Slow e r 0 to 60

L o w e r M P G II I : F a ster 0 to 6 0

L o w e r M P G Hy b r id s 

### 70

Di esels

Fr ont

Rear 

### 60

50 4w d



### 40

30

20

10

0

Fi gur e 41



## com p ared to the average 0 to 60 tim e and m pg. The vehicles in Quadrant I, for exam ple, have

faster than average 0- to-60 tim e and higher than average fuel econom y, but this quadrant

accounts for only six percent of all 2007 car sales and 18 percent of all truck sales. Over 60

percent of all front wheel drive car sales are in Quadrant II (the Slower/Higher one), as are onehalf of the FW D truck sales, but only two percent of the rear drive and two percent of 4wd cars.

Over three fourths of the rear drive cars and ove r half of the 4wd cars are in Quadrant III ( the

Faster/Lower one) as are half of the rear and f our wheel drive trucks. Sim ilar data for 0-to-60

tim e and Laboratory Ton MPG are presented in Figures 42 and 43 and Tables 13 and 14.

Table 12

**Distribution of MY2007 Truck Sales**

**By technology, 0-to-60 time and Lab 55/45 M**

**0 to 60 time <9.7 Sec**  **>9.7 sec <9.7 sec**  **>9.7 sec**

**Lab 55/45 MPG >22.1 MPG**  **>22.1 MPG <22.1 MPG**  **<22.1 MPG**

**Vehicle** Quadrant Quadrant Quadrant Quadrant

**Technology** I II III IV

Front Drive 49% 51% 0% 0%

Rear Drive 6% 9% 50% 35%

4wd 9% 15% 51% 24%

Hybrids 80% 20% 0% 0%

Diesels 98% 0% 0% 2%

All Trucks 18% 22% 39% 21%



## 44

# Laboratory Ton-MPG v s 0 to 60 Tim e

MY2007 Cars

Labor a t or y

Ton-M P G

10 0

80

60

40

20

0

4 6 8 1 0 1 2 1 4

0 to 6 0 Ti me (Sec .) I : F ast er 0 t o 60

Hig h e r T o n- M PG I I : S l ow er 0 to 6 0

High er T o n- M P G

IV: Slow er 0 t o 60

L o w e r T o n- M P G III: Fa st er 0 to 6 0

L o w e r T o n

- M PG



### Fi gur e 4 2



# Laboratory Ton-MPG v s 0 to 60 Tim e

MY 2007 Trucks

Labor a t or y

Ton- M P G

10 0

80

60

40

20

0

4 6 8 10 12 1 4

0 t o 6 0 T i me (S ec .) I: F ast er 0 t o 6 0

High er T o n- M P G II: S l o w er 0 t o 6 0

H i gh er T on- M P G

I V : S l ow er 0 to 6 0

Lo w e r T o n

- M PG II I: F a s t er 0 to 60

L o w e r T o n

- M P G



### Fi gur e 4 3



## 45 Hy br id s

D i esels

F r ont

R ear

4w d

Hy br ids

D i esels

F r ont

R ear

4w dTable 13

**Distribution of MY2007 Car Sales**

**By technology, 0-to-60 time and Lab Ton-MPG**

**0 to 60 time <9.5 Sec**  **>9.5 sec <9.5 sec**  **>9.5 sec**

**Lab Ton-MPG >53.8 Ton-MPG**  **>53.8 Ton-MPG <53.8 Ton-MPG**  **<53.8**

**Ton-MPG**

Vehicle Quadrant Quadrant Quadrant Quadrant

Technology I II III IV

Front Drive 6% 46% 25% 23%

Rear Drive 1% 2% 78% 19%

4wd 0% 5% 54% 41%

Hybrids 3% 97% 0% 0%

Diesels 60% 40% 0% 0%

All Cars 4% 36% 37% 23%

Table 14

**Distribution of MY2007 Truck Sales**

**By technology, 0-to-60 time and Lab Ton-MPG**

**0 to 60 time <9.5 Sec**  **>9.5 sec <9.5 sec**  **>9.5 sec**

**Lab Ton-MPG >53.8 Ton-MPG**  **>53.8 Ton-MPG <53.8 Ton-MPG**  **<53.8**

**Ton-MPG**

Vehicle Quadrant Quadrant Quadrant Quadrant

Technology I II III IV

Front Drive 39% 27% 10% 24%

Rear Drive 20% 19% 36% 25%

4wd 19% 9% 41% 31%

Hybrids 80% 20% 0% 0%

Diesels 100% 0% 0% 0%

All Trucks 25% 16% 32% 27%



## 46

## The increasing trend in Ton-MPG shown in Table 1 can be attributed to better vehicle

design, including m o re efficient engines, better transm ission designs, and better m atching of the

engine and transm ission. Powertrains are m atched to the load better when the engine operates

closer to its best efficiency point m o re of the tim e. For m any conventional engines, this point is

approxim a tely 2000 RPM and 2/3 of the m a xim u m torque at that speed. One way to m a ke the

engine operate m o re closely to its best efficiency point is to increase the num ber of gears in the

transm ission and, for autom atic transm issions, em ploying a lockup torque converter. Three

im portant changes in transm ission design have occurred in recent years:

1) the use of additional gears for both autom atic and m anual transm issions,

2) for the autom a tics, conversion to lockup (L3, L4, L5, L6 and now L7) torque

converter transm issions, and

3) the use of continuously variable transm issions (CVTs).

Table 15 com p ares Ton-MPG by transm ission and vehicle type for 1988, the peak year

for passenger car fuel econom y, and this year. In 1988, every transm ission type shown in the

table achieved less than 40 Ton-MPG. This year, nearly every transm ission type achieves at

least 40 Ton-MPG. Figures 44 to 47 indicate that the L4 transm ission is losing its position as the

predom inant transm ission type for all vehicle classes. Use of the L4 transm ission for cars

peaked at about 80 percent in 1999 and is now down to 45 percent. Sim ilarly, its use peaked at

over 90 percent in 1996 for SUVs and has dropped below the 40 percent level. Over half of this

year = s pickups will still have L4 transm issions, as will about 60 percent of the vans. W h ere

m anual transm issions are used, the 5-speed (M5) transm ission now predom inates.

Transm issions alter the ratio of engine speed to drive wheel speed. In conventional

transm issions, this speed ratio is lim ited to a fixed num ber of discrete values, but for a CVT, the

ratio is continuous. These transm issions differ from conventional autom atic transm issions and

m a nual transm issions in that CVTs do not have a fixed num ber of gears with the advantage that

the engine speed/drive wheel speed ratio can be altered to enhance vehicle perform ance or fuel

econom y in ways not available with conventional transm issions.

More data stratified by transm ission type can be found in Appendix I.

47

### T r an sm i ssi o n S al es F r a ct i o n

( T h r ee Y ear M o vi n g A ver a g e)

Ca r s

S al es F r a ct i o n 100%

80%

60%

40%

20%

0%

1979 1984 1989 1994 1999 2004 M5

A3

Ot he r L4 M4

L6 L3

L5 CV T

M ode l Y e a r

F

i g u r e 4 4



### T r ansm i s si o n S al es Fr act i o n

( T h r ee Y e ar M o v i n g A ver ag e )

SU V s

Sa l e s F r a c t i o n 100%

80 %

60 %

40 %

20 %

0%

1980 198 5 1990 19 95 2000 2005 L4

L5 M5 M4

A3 M3

L3

Ot h e r CV T

M o d el Y ear

F ig u r e 4 6 

### T r a n sm i ssi on S a l e s Fr act i o n

( T h r ee Y ear M o vi n g A v er ag e)

Va n s

S al es F ract i o n 100%

80%

60%

40%

20%

0%

198 0 1984 1988 1992 1996 2000 2004 A3 L3

L4

L5 M5 M4 Ot he r

M o d el Y ear

F igur e 4 5



### T r an sm i ssi o n S al es F r a ct i o n

( T h r ee Y ear M o vi n g A ve r ag e)

P i cku p s

S a le s F r a c t ion

100%

80 %

60 %

40 %

20 %

0%

1980 1985 19 90 1995 2 000 2005 L4

L5 M5 M4

A3 M3

Ot he r

M ode l Y e a r

F igur e 4 7



## 48Table 15

**Ton-MPG by Transmission and Vehicle Type**

**(Conventionally Powered Vehicles)**

**Car Van**  **SUV Pickup** 

**Trans 1988**  **2007 1988**  **2007 1988**  **2007 1988**  **2007**

M4 37.0

-- 33.6

-- 38.0

-- 32.4

--

M5 37.7 40.8 37.7

-- 33.1 41.2 35.3 39.9

M6

-- 38.9

-- -- -- 36.5

-- 37.7

CVT

-- 44.3

-- 42.9

-- 41.6

-- --

L3 36.1

-- 37.1

-- 33.5

-- 31.4

--

L4 37.9 41.3 36.6 42.7 33.8 41.8 33.8 42.5

L5

-- 42.6

-- 45.1

-- 40.9

-- 38.4

L6

-- 42.3

-- -- -- 44.1

-- 44.0



## Table 16 and Figures 48 through 51 com p are horsepower (HP), displacem ent

(CID), and specific power or horsepower pe r cubic inch (HP/CID) for cars, vans,

SUVs, and pickups. For all four vehicle types, significant CID reductions occurred

in the late 1970s and early 1980s. Engine displacem ent has been flat for cars and

vans since the m i d-1980s and has been flat for SUVs since the m i d-1990s, but has

been increasing for two decades for pickups. Average horsepower has increased

substantially for all of these vehicle types since 1981 with the highest increase

occurring for pickups whose HP is now m o re than double what it was then (i.e., 268

versus 115 HP). Light-duty vehicle engines, thus, have also im proved in specific

power with the highest specific power being for engines used in passenger cars.

Table 16

MY2007 Engine Characteristics by Vehicle Type

Vehicle HP CID HP/ Multi- Variable Cylinder

Type CID Valve Valve Deactivation

Car 200 176 1.16 82% 68% 3%

Van 224 217 1.04 51% 46% 12%

SUV 242 232 1.06 67% 53% 11%

Pickup 268 287 0.93 42% 46% 14%

All 223 210 1.09 70% 59% 8%



## 49

### Ca r Ho r s e p o w e r

, CI D

a nd H or s e p ow e r pe r C I D

( T h r ee Y ear M o vi n g A ver ag e)

HP

, CI D HP / CI

D

36 0

CI D

HP H P /C ID 1. 2

32 0 1. 1

28 0 1. 0

24 0 0. 9

20 0 0. 8

16 0 0. 7

12 0 0. 6

80 0. 5

40 0. 4

19 7 5 1980 1985 1 9 9 0 1 9 9 5 2000 2005

M ode l Y e a r

Fi g u r e 4 8



### SUV H o r s e p o w e r

, C I D

a n d H o r s epo w er p e r C I D

( T h r ee Y ear M o v i n g A ve r ag e)

HP

, CI D H P /C ID

36 0

HP

HP / CI

D CI D 1. 2

32 0 1. 1

28 0 1. 0

24 0 0. 9

20 0 0. 8

16 0 0. 7

12 0 0. 6

80 0. 5

40 0. 4

197 5 19 80 1985 19 90 1 995 20 00 200 5

M ode l Y e a r

Fi g u r e 5 0 

### V a n H or s e pow e r

, C I D

an d H o r sep o w er p er C I D

( T h r ee Y ea r M o vi n g A ve r ag e)

HP

, C I D H P /C ID

360

CI D

HP

H P /C ID 1. 2

320 1. 1

280 1. 0

240 0. 9

200 0. 8

160 0. 7

120 0. 6

80 0. 5

40 0. 4

1 975 1 980 1985 1990 199 5 2 000 2005

M o d el Y ear

F

ig u r e 4 9



### P i c k up H or s epow e r

, C I D

a nd H or s e pow e r p e r C I D

( T h r ee Y e ar M o vi n g A v er ag e)

HP

, CI D H P /C ID

360 1. 2

320 1. 1

280 1. 0

240 0. 9

200 0. 8

160 0. 7

120 0. 6

80 0. 5

40 0. 4

1 975 1980 1985 19 90 1995 2 000 20 05

M ode l Y e a r

F

igur e 5 1 CI D

HP

H P

/C ID



## 50

## Table 17 compares CID, HP, and HP/CID by vehicle type and number of cylinders for

model years 1988 and 2007. Table 17 shows that the increase in horsepower shown for the fleet

in Table 9 extends to all vehicle type and cylinder number strata. These increases in horsepower

range from 50 to over 90% . Because displacement has remained relatively constant, it can be

seen that the primary reason for the horsepower increase is increased specific power

C up

between 44 and 88% from 1988 to 2007.

At the number-of-cylinders level of stratification, model year 2007 cars consistently

achieve higher specific power than vans, SUVs or pickups. One reason for the lower specific

power of some truck engines is that these vehicles may be used to carry heavy loads or pull

trailers and thus need more A torque rise, @ (i.e., an increase in torque as engine speed falls from

the peak power point) to achieve acceptable drivability. Engines equipped with four valves per

cylinder typically have inherently lower torque rise than two valve engines with lower specific

power.

.

Table 17

**Changes in Horsepower and Specific Power**

**by Vehicle Type and Number of Cylinders**

**Vehicle HP HP Percent CID CID Percent HP/CID HP/CID Percent**

**Type Cyl. 1988 2007 Change 1988 2007 Change 1988 2007 Change**

Cars 4 95 151 59% 118 127 8% 0.805 1.186 47%

6 142 236 66% 193 206 7% 0.744 1.152 55%

8 164 316 93% 301 310 3% 0.544 1.021 88%

Vans 4 98 150 53% 145 148 2% 0.678 1.014 50%

6 149 224 50% 213 216 1% 0.722 1.039 44%

8 168 295 76% 322 325 1% 0.520 0.908 75%

SUVs 4 94 163 73% 122 142 16% 0.773 1.146 48%

6 147 233 59% 211 216 2% 0.706 1.081 53%

8 183 308 68% 338 317 -6% 0.541 0.971 80%

Pickups 4 97 165 70% 142 163 15% 0.685 1.009 47%

6 142 221 56% 229 236 3% 0.644 0.943 46%

8 180 299 66% 329 321 -2% 0.544 0.928 71%



## 51Table 18

**Improvement in Horsepower and Specific Power**

**by Vehicle Type and Inertia Weight**

**Inertia HP**  **HP Percent**  **CID CID**  **Percent HP/CID HP/CID**  **Percent**

**Weight 1988 2007 Change**  **1988 2007 Change**  **1988 2007**  **Change**

Cars

2250 73 199 173% 90 110 22% 0.808 1.810 124%

2500 78 106 36% 100 91 -9% 0.785 1.165 48%

2750 97 116 20% 123 101 -18% 0.804 1.145 43%

3000 114 135 18% 145 118 -19% 0.797 1.141 43%

3500 151 191 26% 212 163 -23% 0.732 1.185 62%

4000 160 245 53% 289 211 -27% 0.569 1.179 107%

4500 144 304 111% 305 302 -1% 0.474 1.007 113%

5000 207 296 43% 408 268 -34% 0.509 1.093 115%

5500 205 299 46% 412 236 -43% 0.498 1.258 153%

6000 205 449 119% 412 329 -20% 0.498 1.326 167%

**Inertia HP**  **HP Percent**  **CID CID**  **Percent HP/CID HP/CID**  **Percent**

**Weight 1988 2007 Change**  **1988 2007 Change**  **1988 2007**  **Change**

Vans

4000 149 181 21% 214 196 -8% 0.717 0.929 30%

4500 169 233 38% 320 219 -32% 0.528 1.070 103%

5000 156 210 35% 312 272 -13% 0.500 0.769 54%

5500 195 295 51% 346 325 -6% 0.562 0.908 61%

6000 126 295 134% 379 325 -14% 0.332 0.908 173%

**Inertia HP**  **HP Percent**  **CID CID**  **Percent HP/CID HP/CID**  **Percent**

**Weight 1988 2007 Change**  **1988 2007 Change**  **1988 2007**  **Change**

SUVs

3500 147 164 12% 210 148 -30% 0.712 1.109 56%

4000 135 203 50% 190 190 0% 0.723 1.081 50%

4500 147 243 65% 311 224 -28% 0.494 1.094 122%

5000 181 259 43% 330 256 -22% 0.545 1.027 89%

5500 200 315 58% 350 295 -16% 0.572 1.085 90%

6000 162 321 98% 368 329 -11% 0.445 0.979 120%

**Inertia HP**  **HP Percent**  **CID CID**  **Percent HP/CID HP/CID**  **Percent**

**Weight 1988 2007 Change**  **1988 2007 Change**  **1988 2007**  **Change**

Pickups

3500 129 156 21% 183 163 -11% 0.719 0.964 34%

4000 154 201 31% 282 216 -23% 0.555 0.936 68%

4500 174 235 35% 322 238 -26% 0.539 0.995 85%

5000 193 262 36% 342 294 -14% 0.565 0.886 57%

5500 178 302 70% 363 323 -11% 0.495 0.932 88%

6000 140 318 127% 379 330 -13% 0.369 0.960 160%



## Table 18 shows sim ilar data to that in Table 17, but the stratification is based on inertia

weight. This table clearly shows that, for every case for which a com p arison can be m ade

between 1988 and 2007, there were increases in HP, substantial increases in specific power

ranging from 30 to 170%, and with just m i nor exceptions, substantial decreases in CID.

52

### H P /C ID b y N u m b e r o f V a lv e s P e r C y lin d e r

( T h r ee Y ear M o v i n g A v er ag e)

Ca r s

H P /C ID

1. 2

1. 0

0. 8

0. 6

0. 4 4- V al v e

3- V al v e

2- V a l v e 4- V al v e

3- V al v e

2- V a l v e

19 80 1985 1 990 199 5 2000 200 5

M o d el Y ear

F

i g ur e 5 2



### H P /C ID b y N u m b e r o f V a lv e s P e r C y l in d e r

( T h r e e Y e ar M o vi n g A ve r ag e)

SU V s

H P /C ID

1. 2

1. 0

0. 8

0. 6

0. 4 4- V al v e

3- V al v e

2- V al v e 4- V al v e

3- V al v e

2- V al v e 

### H P /C ID b y N u m b e r o f V a lv e s P e r C y lin d e r

( Thr e e Y e ar M o vi ng A v er a g e )

Va n s

H P /C ID

1. 2

1. 0

0. 8

0. 6

0. 4 4- V al v e

3- V al v e

2- V a l v e 4- V al v e

3- V al v e

2- V a l v e

1 980 1985 19 90 1 995 200 0 20 05

Mo d e l Y e a r

Fi g u r e 5 3



### H P / C I D b y N u m b e r o f V a lv e s P e r C y li n d e r

( T hr ee Y ear M o vi n g A v er a g e)

P i c k ups

HP / C I D

1. 2

1. 0

0. 8

0. 6

0. 4 4- V a l v e

2- V a l v e 3- V al v e 4- V a l v e

2- V a l v e 3- V al v e

198 0 19 85 1 990 1 995 2 00 0 200 5 198 0 1 985 19 90 1 99 5 20 00 20 05

Mo d e l Y e a r Mo d e l Y e a r

Fi g u r e 5 4 Fi g u r e 5 5



## 53

### N u m b e r o f V al ves p er C yl i n d er 

### N u m b e r o f V a lv e s p e r C y lin d e r

( T h r ee Y ear M o v i ng A v e r ag e) 

### ( T h r ee Y e ar M o vi n g A ver ag e )

Ca r s 

### Va n s

1988 1992 1996 2000 2 0 04 0% 20% 40% 60% 80% 100% S a l es F ract i o n

Fi v

e F our Thr e e Tw o

1988 1992 1996 2000 2004 0% 20 % 40 % 60 % 80 % 100% S al es F ra ct i o n

F

our Th r e e Tw o

M ode l Y e a r M ode l Y e a r

F igur e 5 6 F igur e 5 7



### N u m b er o f V al ves p er C yl i n d e r N u m b e r o f V a lv e s p e r C y lin d e r 

### ( T h r ee Y e a r M o vi n g A ver ag e) ( T h r ee Y e ar M o vi n g A ver ag e )



### SU V s P i c k ups

S al es F ract i o n

Tw o

Th r e e

F our

1988 1992 1996 20 00 20 04

Mo d e l Y e a r M ode l Y e a r

F igur e 5 8 F igur e 5 9 1988 1992 19 96 2000 20 0 4 0% 20% 40% 60% 80% 100%

F our Thr e e Tw o

0% 20% 40% 60% 80% 100% S al es F r act i o n



## 54

## Figures 52 through 55 show that increases in HP per CID apply to all of the engines,

except for a couple of case for engines with three valves. Engines with m o re valves per cylinder

deliver higher values of HP per CID. Engines with only two valves per cylinder deliver

substantially m o re horsepower per CID then they used to, typically about a 50 percent increase

for the tim e period shown. The increases in HP and HP-per-CID is due to changes in engine

technologies. Figures 56 through 59 show that usage of m u lti-valve engines is increasing for all

vehicle types and as shown in Table 16 for MY2007, is now over 80 percent for cars, nearly 70

percent for SUVs, and about 45 percent for pickups and vans.

Figures 60 and 61 and Table 19 show how the car and truck fleet have evolved from one

that consisted alm o st entirely of carbureted engine s to one which is now alm o st entirely port fuel

injected, with a clear trend towards increased use of variable valve tim ing. In 1975, about 95

percent of all cars had carburetors as did alm o st all of the trucks, by 1988 use of carburetors had

dropped below the 20 percent level for all vehicle types. For MY2007, nearly 70 percent of cars

have m u lti-valve, port fuel injected engines with variable valve tim ing, as do about half of

SUVs, vans, and pickups.

C a r S a l e s Fr a c t i on by E ngi ne Ty pe Tr uc k S a l e s Fr ac t i on by E ngi ne Ty p e 

### ( T hr ee Y ear M o vi n g A v er ag e) ( T h r ee Y ear M o vi n g A ver a g e)

S al es F ract i o n S al es F r act i o n 100% 100%

80% 80 %

60% 60 %

40% 40 %

20% 20 %

0% 0% D i ese l

Ca r b

. TB I

.

P o rt VVT Po r t F i x e d

Va l v e D i ese l

TB I

.

Ca r b

.

P o rt VVT Po r t F i x e d

Va l v e

1976 19 8 0 1984 1988 1992 1996 20 0 0 2004 1976 1980 1 984 1988 1992 1996 2 000 2004

Mo d e l Y e a r M ode l Y e a r

F i g u re 60 F i g u re 61



## 55T able 19

**Sales Fraction of MY1988 and MY2007 Light Vehicles**

**by Engine Type and Valve Timing**

**Engine Type Cars**  **Vans SUVs**  **Pickups All** 

**1988 2007**  **1988 2007**  **1988 2007 1988**  **2007 1988**  **2007**

Carb 16%

--- <1%

--- 16%

--- 16%

--- 15%

---

TBI 30%

--- 43%

--- 37%

--- 48%

--- 34%

---

Port Fixed 54% 32% 57% 54% 47% 47% 36% 54 51% 41%

Port Variable

--- 65%

--- 46%

--- 51%

--- 46

--- 57%

Diesel <1% <1% <1%

--- <1% <1% <1%

--- <1% <1%

Hybrids

--- 3%

--- --- --- 2%

--- <1%

--- 2%



## For over a decade and an half, autom o tive m a nufacturers have been using engines which

use either cam s or electric solenoids to provide variable intake and/ or exhaust valve tim ing and

in som e cases valve lift. Conventional engines use cam shafts which are perm anently

synchronized with the engine' s crankshaft so that they operate the valves at a specific fixed point

in each com bustion cycle regardless of the speed and load at which the engine is operated. The

ability to control valve tim ing allows the design of an engine com bustion cham ber with a higher

com p ression level than in engines equipped with fixed valve tim ing engines which in turn

provides greater engine efficiency, m o re power and im proved com bustion efficiency. Variable

valve tim ing (VVT) also allows the valves to be operated at different points in the com bustion

cycle, to provide perform ance that is precisely tailored to the engine' s specific speed and load at

any given instant with the valve tim ing set to allow the best overall perf orm ance across the

engine' s norm al operating range. This results in im proved engine efficiency under low-load

conditions, such as at idle or highway cruising, and increased power at tim es of high dem a nd. In

addition, variable valve tim ing can result in reduced pum ping losses, from the work required to

pull air in and push exhaust out of the cylinder.

Because autom obile m anufacturers are not currently required to provide EPA with data

on the type of valve tim ing their engines have, the data base used to generate EPA = s fuel

econom y trend report was augm ented to indicate whether a vehicle had fixed or variable valve

tim ing. The data augm entation was based on data from trade publications and data published by

autom o tive m anufacturers. In addition, no differentiation between engines which used cam s or

solenoids to control the valve tim ing was m ade, nor was valve lift considered. For cars, the

augm ented data covers m odel years 1989 to 2007, while for trucks the augm entation covered

m odel years 1999 to 2007.

56Table 20

**Comparison of MY1988 and MY2007 Cars**

**by Engine Fuel Metering, Number of Valves and Valve Timing**

**Fuel Number**  **Valve Horsepower**  **CID HP/CID**  **Ton MPG 0 to 60** 

**Metering of**  **Timing Time** 

**Valves**

**1988 2007 1988 2007**  **1988 2007 1988**  **2007 1988 2007** 

Carb Fixed 88

--- 131

--- .75

--- 37.2

--- 14.3

---

TBI 2 Fixed 97

--- 141

--- .71

--- 36.9

--- 13.7

---

Port 2 Fixed 136 261 193 285 .74 .92 36.6 40.4 11.9 8.6

Port 4 Fixed 137 189 131 162 1.05 1.18 37.9 40.2 11.1 9.8

Port 4 Variable

--- 194

--- 157

--- 1.22

--- 42.6

--- 9.6

**Percent Change over 1988 Port Two Valve, Fixed Valve Timing**

Carb Fixed -35%

--- -32%

--- 1%

--- 2%

--- 20%

---

TBI 2 Fixed -29%

--- -27%

--- -4%

--- 1%

--- 15%

---

Port 2 Fixed 0% 92% 0% 48% 0% 24% 0% 10% 0% -28%

Port 4 Fixed 1% 38% -32% -16% 42% 59% 4% 10% -7% -18%

Port 4 Variable

--- 43% --- -19%

--- 65%

--- 16%

--- -19%



## Table 20 com p ares horsepower, engine size (C ID), specific power (HP/CID), Ton- m pg,

and estim ated 0-to-60 acceleration tim e for five selected MY1988 and 2007 engine types.

Because 1988 was the peak year for car fuel econom y, and because the two valve, fixed

valve tim ing, port injected engine accounted for about half of the car engines built that year, it

was selected as a base line engine with its average characteristics com p ared to those for the

MY2007 two- and four-valve, fixed valve tim ing and four- valve VVT engines. As shown in

Figure 62, all three of these MY2007 engine types had substantially higher horsepower than the

baseline MY1988 engine, but the MY2007 four valve engines fixed and VVT engines are

considerably sm aller and have substantially higher specific power. Not all of these

im provem ents in engine design for these engine types that occurred between 1988 and 2007

were used to im prove fuel econom y as indicated by the nom inal 20 percent decrease in 0-to-60

tim e each achieved. As m entioned earlier, in this report vehicle perform ance for conventionally

powered vehicles is determ ined by an estim ate of 0-to-60 acceleration tim e calculated from the

ratio of vehicle power to weight. Obtaining incr eased power to weight in a tim e when weight is

trending upwards im plies that horsepower is incr easing. Increased horsepower can be obtained

by increasing the engine = s displacem ent, the engine = s specific power (HP/CID), or both.

Increasing specific power has been the prim ary driver for increases in perform ance for the past

two decades.

57Per cent D i f f eren ce i n M Y 2007 Veh i cl e C h aract er i st i cs

F r om M Y 1988 Por t 2 Val v e F i xed C ar En g i n e

Perce nt Ch an ge

100 %

M Y 2 0 0 7 E n gi ne T y pe

P o rt 4 Valve Var i a b le

80 % P o rt 4 Valve F ix e d

P o rt 2 Valve F ix e d

60 %

40 %

20 %

0%

-20%

-40%

T o n M P G 0 to 60 T im e HP CID H P/CID Fi gure 62



## For the current m odel year fleet, specific power has been studied at an even m o re detailed

level of stratification with both car and truck engines being classified according to: (1) the

num ber of valves per cylinder, (2) the m anufacturer = s fuel recom m endation, (3) the presence or

absence of an intake boost device such as a turbocharger or supercharger and (4) whether or not

the engine had fixed or variable valve tim ing. (See Tables 21 and 22.) Higher HP/CID is

associated with: (a) m o re valves per cylinder, (b) higher octane fuel, (c) intake boost and (4) use

of variable valve tim ing. The technical approaches result in specific power ranges for cars and

trucks from about .9 to about 1.7. The relative sa les fractions in Tables 21 and 22 are just for

each technical option in the table and exclude hybrids.

Tables 21 and 22 show the increm ental effect, on a sales weighted basis, of adding each

technical option, but not all of the technical options are sales significant. The effect of the use of

higher octane fuel cannot be discounted, because roughly 20 percent of the current car fleet is

com p rised of vehicles which use engines for which high octane fuel is recom m e nded. By

com p arison, about 12 percent of this year = s light trucks require prem ium fuel.

Engine technology which delivers im proved specific power thus can be used in m a ny

ways ranging from reduced displacem ent and im proved fuel econom y at constant (or worse)

perform ance, to increased perform ance and the sam e fuel econom y at constant displacem ent.

58Table 21

**HP/CID and Sales Fraction by Fuel and Engine Technology**

**Model Year 2007 Cars**

**Number of Valves per Cylinder**

**Fuel/Boost/Valves Two**  **Three Four**  **Five Total** 

**HP/CID Sales HP/CID Sales**  **HP/CID Sales HP/CID Sales**  **Sales**

**Fract. Fract.**  **Fract. Fract.**  **Fract.**

Regular/No Boost/FIX .88 .088

---- ---- 1.11 .175 1.35

---- .263

Regular/No Boost/VVT 1.02 .077 1.07 .010 1.15 .414

---- ---- .501

Regular/Boost /FIX

---- ---- ---- ---- ---- ---- ---- ---- .000

Regular/Boost /VVT

---- ---- ---- ---- 1.52 .001

---- ---- .001

Premium/No Boost/FIX 1.16 .013 .89 .001 1.22 .013 1.35

---- .027

Premium/No Boost/VVT

---- ---- ---- ---- 1.31 .160

---- ---- .160

Premium/Boost /FIX 1.08 .001 1.52 .001 1.62 .028

---- ---- .030

Premium/Boost /VVT

---- ---- 1.52

---- 1.67 .017

---- ---- .017

Diesel/No Boost

---- ---- ---- ---- ---- ---- ---- ---- .000

Diesel/Boost

---- ---- ---- ---- 1.16 .001

---- ---- .001

Total .179 .012 .808

---- 1.000

Table 22

**HP/CID and Sales Fraction by Fuel and Engine Technology**

**Model Year 2007 Trucks**

**Number of Valves per Cylinder**

**Fuel/Boost/Valves Two**  **Three Four**  **Five Total** 

**HP/CID Sales HP/CID Sales**  **HP/CID Sales HP/CID Sales**  **Sales**

**Fract. Fract.**  **Fract. Fract.**  **Fract.**

Regular/No Boost/FIX 0.90 0.371 1.04 0.009 1.10 0.099

---- ---- 0.480

Regular/No Boost/VVT 0.97 0.027 0.91 0.056 1.10 0.310

---- ---- 0.393

Regular/Boost /FIX

---- ---- ---- ---- ---- ---- ---- ---- 0.000

Regular/Boost /VVT

---- ---- ---- ---- 1.53 0.001

---- ---- 0.001

Premium/No Boost/FIX 1.02 0.006 0.99 0.001 1.18 0.012

---- ---- 0.019

Premium/No Boost/VVT 1.06 0.012

---- ---- 1.18 0.088

---- ---- 0.100

Premium/Boost /FIX

---- ---- 1.48

---- ---- ---- ---- ---- 0.000

Premium/Boost /VVT

---- ---- 1.35

---- 1.70 0.005

---- ---- 0.005

Diesel/No Boost

---- ---- ---- ---- ---- ---- ---- ---- 0.000

Diesel/Boost 1.03

---- ---- ---- 1.18 0.002

---- ---- 0.002

Total 0.417 0.066 0.517

---- 1.000



## 59

## A recent engine developm ent has been the reintroduction of cylinder deactivation, an

autom o tive technology that was used by General Motors in som e MY1981 V-8 engines that

could be operated in 8- , 6- and 4-cylinder m odes. This approach, which has also been called by

a num ber of nam e s including > variable displacem ent =

, > displacem ent on dem and =

, > active fuel

m a nagem e nt = and > m u ltiple displacem ent = , involves allowing the valves of selected cylinders of

the engine to rem ain closed and interrupting the fuel supply to these cylinders when engine

power dem ands are below a predeterm i ned threshold, as typically happens under less dem anding

driving conditions, such as steady state operation. Under light load conditions, the engine can

thus provide better fuel m ileage than would otherwise be achieved. Although frictional and

therm odynam i c energy losses still occur in the cylinders that are not being used, these losses are

m o re than offset by the increased load and reduced specific fuel consum ption of the rem a ining

cylinders. Typically half of the usual num ber of cylinders are deactivated. Challenges to the

engine designer for this type of engine incl ude m ode transitions, idle quality, and noise and

vibration. For MY2007, as shown previously in Table 16, it is estim ated that about three percent

of cars and about 12 percent of trucks are equipped with cylinder deactivation.

Table 23

**Comparison of MY2007 Cars with Engines with Cylinder Deactivation**

**Car Model Name**  **Drive Trans**  **Inertia Engine**  **Lab. Cyl.**  **Pct. Change**

**Class Weight**  **CID HP**  **55/45 Deact.**  **HP MPG** 

Midsize Grand Prix Front L4 4000 325 290 25.1 Yes 16% -2%

Car Grand Prix 231 250 25.5 No

Large Impala Front L4 4000 325 290 24.7 Yes 21% -4%

Car Impala 237 240 25.6 No

300 AWD 4wd L5 4500 348 340 23.1 Yes 34% 1%

300 AWD 215 253 22.8 No

Midsize Magnum AWD 4wd L5 4500 348 340 23.1 Yes 34% 1%

Wagon Magnum AWD 215 253 22.8 No



## 60Table 24

**Comparison of MY2007 Trucks with Engines with Cylinder Deactivation**

**Truck Model Name**  **Drive Trans**  **Inertia Engine**  **Lab. Cyl.**  **Pct. Change**

**Class Weight**  **CID HP**  **55/45 Deact.**  **HP MPG** 

Midsize Odyssey Front L5 4500 212 244 25.0 Yes 0% 5%

Van Odyssey 212 244 23.9 No

Midsize Grand Cherokee Rear L5 5000 348 345 19.5 Yes 50% -1%

SUV Grand Cherokee 287 230 19.7 No

Large Envoy 4wd L4 5000 325 280 20.0 Yes 2% -3%

SUV Envoy 254 275 20.6 No

Durango Rear L5 5000 348 345 19.5 Yes 47% 7%

Durango Rear L5 5000 287 235 18.3 No

Large Ram 1500 Rear L5 5000 348 345 19.5 Yes 47% 7%

Pickup Ram 1500 287 235 18.3 No

Ram 1500 4wd L5 5500 348 345 18.8 Yes 47% 11%

Ram 1500 287 235 17.0 No



## Table 23 com p ares exam ples of individual MY2007 car m odels with cylinder deactivation with

their sam e-m odel counterparts with optional sm aller engines that do not incorporate cylinder

deactivation. For every case in the table, the version of the m odel equipped with cylinder

deactivation has horsepower ratings that are significantly higher and about the sam e fuel

econom y. Som e of the truck exam ples in Table 24 indicate that m odels equipped with cylinder

deactivation can achieve both higher horsepower and fuel econom y than their counterparts.

The data in Tables 23 and 24 indicate cylinder deactivation can be used to increase fuel econom y

at constant horsepower, or to m aintain equivale nt fuel econom y at higher horsepower levels, or,

in som e cases, to increase both horsepower and fuel econom y.

61

# Car Technology Penetration

Y ears After Fi rst Si gnifi cant Use

Sales Fract ion



### 10 0%

75 %

50 %

25 %

0%

0 5 10 15 20 25 30 35

Ye ars Por t FI Lockup

Front Driv e Mul t iv a l v e

V ariab le

Valv e

C ont inu ously Varia b le Transm ission



### Fi gu r e 6 3



## Figure 63 com p ares penetration rates for six passenger car technologies, nam ely port fuel

injection (Port FI), f r ont-wheel drive (FW D ), m u lti-valve engines (i.e., engines with m o re than

two valves per cylinder), lockup transm issions, engines with variable valve tim ing, and CVTs.

The sales fraction for VVT car engines has increased in a sim ilar fashion to the others shown in

the figure. This indicates that, in the past, it has taken a decade for a technology to prove itself

and attain a sales fraction of 40 to 50 percent and as long as another five or ten years to reach

m axim u m m arket penetration.

62

# Car Technology Penetration

Y ears Afte r Fi rst S i gni f i ca n t Use

Sales Fraction



### 0 5 10 15 20 25 30 35

Ye ars

Figu re 64 0% 25% 50% 75% 100%

TBI L3 L4

Por t 2 Valv e

Fi xed Port 4 Valv e

Fi xed



## A sim ilar com p arison of five technologies whose sales fraction peaked out is shown in

Figure 64. This figure shows that, in the past, it has taken a num ber of years for technologies

such as throttle body fuel injection (TBI), lockup 3-speed (L3) and 4-speed (L4) transm issions to

reach their m axim u m sales fraction, and, even then, use of these technologies has often

continued for a decade or longer. For the lim ited num ber of historical cases studied, the tim e a

given technology has taken to attain and then pass a m arket share of about 40 to 50 percent

appears to be one indicator of whether it later attains a stabilized high level of m arket

penetration. L4 transm issions and both two- and four-valve, port injected, fixed valve tim ing car

engines (Port 2V- and 4V- Fixed) now can be cla ssified with technologies such as TBI engines

and L3 transm issions which have reached their peak sales fractions and, thus, are likely to

disappear from the new vehicle fleet.

63

## Table 25 com p ares inertia weight, the fuel econom y ratings, the ratio of highway to city

fuel econom y, and ton-m pg of the MY2007 hybrid and diesel vehicles with those for the average

conventionally powered MY2007 car and truck. All of the hybrid and diesel vehicles in the

table have a lower highway/city ratio than the average conventional car or truck.

Table 25

**Characteristics of MY 2007 Hybrid and Diesel Vehicles**

**Inertia Lab**  **<----- Adjusted ----->**  **HWY/**

**Model Name Weight**  **CID Trans**  **55/45 City**  **HWY COMP**  **City Ton** 

**MPG MPG**  **MPG MPG**  **Ratio MPG** 

**Hybrid Cars**

Prius 3000 91 CVT 65.8 47.7 45.1 46.2 .95 69.3

Altima 3500 152 CVT 46.7 35.1 33.0 33.9 .94 59.3

Accord 4000 183 L5 36.3 24.4 32.1 28.3 1.31 56.5

Gs 450H 4500 211 L6 30.8 21.9 25.3 23.7 1.15 53.4

Civic 3000 82 CVT 58.8 40.2 45.3 42.9 1.13 64.4

Camry 4000 144 CVT 45.9 33.4 34.1 33.8 1.02 67.6

**Hybrid Trucks**

Vue 3500 145 L4 34.0 23.3 29.3 26.4 1.26 46.2

RX 400H 2WD 4500 202 CVT 35.0 27.5 24.5 25.7 .89 57.9

Mariner 4WD 4000 140 CVT 36.4 27.6 26.7 27.1 .97 54.1

Highlander 4WD 4500 202 CVT 34.3 26.5 24.6 25.4 .93 57.1

Highlander 2WD 4500 202 CVT 35.0 27.5 24.5 25.7 .89 57.9

Escape FWD 4000 140 CVT 40.6 31.3 28.5 29.7 .91 59.3

Escape 4WD 4000 140 CVT 36.4 27.6 26.7 27.1 .97 54.1

RX 400H 4Wd 4500 202 CVT 34.3 26.5 24.6 25.4 .93 57.1

K15 Silverado classic 4WD 5500 325 L4 20.9 14.9 18.0 16.5 1.21 45.5

K15 Sierra classic 4WD 5500 325 L4 20.9 14.9 18.0 16.5 1.21 45.5

C15 Silverado classic 2WD 5000 325 L4 22.3 15.9 19.2 17.6 1.20 44.0

C15 Sierra classic 2WD 5000 325 L4 22.3 15.9 19.2 17.6 1.20 44.0

**Diesel Cars**

R320 CDI 4MATIC 5500 182 L7 28.2 19.0 25.9 22.4 1.36 61.5

E320 BLUETEC 4000 182 L7 34.7 22.8 32.2 27.3 1.41 54.7

**Diesel Trucks**

Touareg 6000 300 L6 21.7 14.8 20.0 17.4 1.35 52.2

GL320 CDI 4MATIC 6000 182 L7 26.1 17.9 23.4 20.7 1.30 62.0

Grand Cherokee 4WD 5000 183 L5 25.1 17.5 22.1 19.8 1.27 49.6

Grand Cherokee 2WD 4500 183 L5 26.0 17.9 23.0 20.5 1.28 46.2

ML320 CDI 4MATIC 5000 182 L7 27.5 18.9 24.4 21.7 1.29 54.2

Average Car 3588 176

-- 29.4 19.5 27.6 23.4 1.42 42.6

Average Truck 4722 245

-- 22.1 15.1 20.4 17.7 1.35 42.0



## 64

## In addition, there are several cases in the table for which the highway to city ratio is less than

1.0, and these represent cases where a vehicle achieves higher fuel econom y in city than in

highway driving. This year = s diesel cars achieve ton-m pg values that are roughly the sam e as

som e of the hybrid cars. For MY2007, the Toyota Prius achieves 79 Ton-m pg, alm o st twice that

of the average car.

All but two of the vehicles in Table 25 (the Toyota Prius and GL320 CDI 4MATIC)

have conventionally powered counterparts. Tables 26 and 27 com p are the adjusted com posite

fuel econom y and an estim ate of annual fuel usage (assum i ng 15,000 m iles per year) for these

vehicles with their conventionally powered (baseline) counterparts. The com p arisons in both

tables are lim ited to a basis of: m odel nam e, drive, inertia weight, transm ission, and engine size

(CID), and for sim p licity there is only one listing for A twin @ vehicles, nam ely: the Escape/

Mariner, the GM C15-K15 Silverado/ Sierra pi ckups and the Highlander/ RX400 H. Differences

in the perform ance attributes of these vehicles com p licate m aking the forward analysis of the

fuel econom y im provem ent potential due to hybridiza tion and dieselization. In particular, hybrid

vehicles are often reported to have faster 0-to-60 acceleration tim es than their conventional

counterparts, while vehicles equipped with diesel engines have higher low-end

Table 26

**Comparison of MY2007 Hybrid Vehicles With Their Conventional Counterparts**

**<----- Hybrid Version ------> <---- Baseline Version --->**  **<Improvement>**

**Model Name Inertia**  **ADJ Gal**  **Inertia ADJ**  **Gal ADJ**  **Gal**

**Weight CID Trans**  **COMP Per**  **Weight CID Trans**  **COMP Per**  **COMP Per** 

**MPG Year** * **MPG Year** * **MPG Year** *

Accord 4000 183 L5 28.3 530 3500 183 L5 22.0 682 29% 152

Altima 3500 152 CVT 33.9 442 3500 152 CVT 26.9 558 26% 115

Civic 3000 82 CVT 42.9 350 3000 110 L5 29.6 507 45% 157

Camry 4000 144 CVT 33.8 444 3500 144 L5 25.4 591 33% 147

Vue 3500 145 L4 26.4 568 3500 134 L4 22.8 657 16% 90

Escape FWD 4000 140 CVT 29.7 505 3500 140 L4 21.9 685 36% 180

3500 140 M5 23.8 630 25% 125

Escape 4WD 4000 140 CVT 27.1 554 3500 140 L4 20.5 732 32% 178

3500 140 M5 22.4 670 21% 116

Highlander 2WD 4500 202 CVT 25.7 584 4000 202 L5 19.9 754 29% 170

Highlander 4WD 4500 202 CVT 25.4 591 4500 202 L5 19.2 781 32% 191

C15 Silverado Classic 2WD 5000 325 L4 17.6 852 5000 325 L4 16.8 893 5% 41

K15 Silverado Classic 4WD 5500 325 L4 16.5 909 5500 325 L4 16.4 915 1% 6

*Note:

Gallons per year calculation is based on all vehicles being driven 15,000 miles.



## 65

## torque, but slower 0-to-60 tim es. In addition, so m e hybrid vehicles use technologies such as

cylinder deactivation and CVT transm issions that ar e not offered in their counterparts. Given the

difficulty in choosing the A right @ baseline vehicle, Table 25 thus typically includes a com p arison

for the CVT-equipped Escape Hybrid with baseline data for both m a nual and autom a tic

transm ission versions of this vehicle.

Fuel econom y im provem ents and fuel savings per year for the hybrid vehicles in Table

26 vary considerably fromabout five percent for the GM pickups to 45 percent for the CVTequipped Civic hybrid. Sim ilarly, fuel econom y im provem e nts for diesels range from 16 to 35

percent, and these vehicles also offer relatively high savings in fuel usage. Several years after

the introduction for sale in the U.S. of the first hybrid vehicle, the MY2000 Honda Insight,

hybrid vehicles now account for over two percent of the com b ined car/truck fleet. In addition,

the sales fraction for diesels rem ains below a quarter of one percent, m o re than an order of

m agnitude sm aller than their 5.9 percent sales fraction in 1981.

Table 27

**Comparison of MY2007 Diesel Vehicles With Their Conventional Counterparts**

**<----- Hybrid Version -----> <----- Baseline Version ----->**  **<Improvement>**

**Model Name Inertia**  **ADJ Gal**  **Inertia ADJ**  **Gal ADJ**  **Gal**

**Weight CID Trans COMP**  **Per Weight**  **CID Trans COMP**  **Per COMP**  **Per**

**MPG Year** * **MPG Year** * **MPG Year** *

E320 BLUETEC** 4000 182 L7 27.3 549 4000 213 L7 20.2 743 35% 193

R320 CDI 4MATIC** 5500 182 L7 22.4 670 5500 213 L7 17.0 882 32% 213

ML320 CDI 4MATIC** 5000 182 L7 21.7 691 5000 213 L7 17.4 862 25% 171

Touareg 6000 300 L6 17.4 862 5500 254 L6 14.8 1014 18% 151

Grand Cherokee 4WD 5000 183 L5 19.8 758 4500 226 L5 17.1 877 16% 120

Grand Cherokee 2WD 4500 215 L5 20.5 732 4500 226 L5 17.7 847 16% 116

*Note:

Gallons per year calculation is based on all vehicles being driven 15,000 miles.

**Note:

Baseline version used for the E320 BLUETEC comparison is the E350. Baseline version used for the R320 CDI

4MATIC comparison is the R350 4MATIC. Baseline version used for the ML320 CDI 4MATIC comparison is the

ML350 4MATIC.



## 66

## VI. Marketing Groups

In its century of evolution, the autom o tive industry existed first as sm all, individual

com p anies that relatively quickly went out of business or grew into larger corporations. In that

context, the historic term > m a nufacturer = usually m eant a corporation that was associated with a

single country that m anufactured vehicles for sale in just that country and perhaps exported

vehicles to a few other countries, too. Over the years, the nature of the autom o tive industry has

changed substantially, and it has evolved into one in which global consolidations and alliances

am ong heretofore independent m anufacturers have becom e the norm

, rather than the exception.

The reports in this series include analyses of fuel econom y trends in term s of the whole

fleet of cars and light trucks and in various s ubcategories of interest, e.g., by weight class, by

size class, etc. In addition, there has been a treatm e nt of trends by groups of m a nufacturers.

Initially, these groups were derived from the A Dom estic @ and A Im port @ categories which are part

of the autom obile fuel econom y standards categorie s. This classification approach evolved into

a m arket segm ent approach in which cars were apportioned to a A Dom estic, @ A European, @ and

A Asian @ category, with trucks classified as A Dom estic @ or A Im ported. @ As the autom o tive

industry has becom e m o re transnational in nature, this type of vehicle classification has becom e

less useful. In this report, trends by groups of m a nufacturers are now used to reflect the

transnational and transregional nature of the autom obile industry. To reflect the transition to an

industry in which there are only a sm all num ber of independent com p anies, the fleet has been

divided into eight m ajor m arketing group segm ents, and an ninth catch-all group ( A Others @ ) that

contains independent m anufacturers not assigned to one of the eight m ajor m arketing groups.

These eight m ajor m arketing groups are:

1) The General Motors Group includes GM, Opel, Saab, Isuzu, and Daewoo;

2) The Ford Motor Group includes Ford, Jaguar, Volvo, Land Rover, Aston Martin, and

Mazda;

3) The Daim lerChrysler Group includes Chrysler and Mercedes Benz;

4) The Toyota Group includes Toyota, Scion and Lexus;

5) The Honda Group includes Honda and Acura;

6) The Nissan Group includes Nissan and Infiniti;

7) The Hyundai-Kia (HK) Group includes Hyundai and Kia; and

8) The VW Group includes Volkswagen, Audi, SEAT, Skoda, Porsche, Lam borghini,

Buggati, and Bentley.

67

## Taken together, the eight m ajor m arketing groups com p rise over 95 percent of the MY2007 new

vehicle m arket in the U.S. It is expected that these m arketing groups will continue to evolve and

perhaps expand, or possibly contract as further changes in the autom o tive industry occur. For

exam ple, GM sold nearly its entire interest in Suzuki in 2006, and so Suzuki has been deleted

from the GM m arketing group in this year’s report. More recently, Ford sold its interest in

Aston Martin, and Daim ler sold m o st of its stake in Chrysler.

Table 28 com p ares laboratory fuel econom y values for the m arketing groups described

above for m odel year 2007 with the overall fleet average. For each m arketing group, the table

also shows the effect of adding certain individua l m anufacturers in that group. For exam ple, if

just GM cars were considered, the GM group would have an average laboratory car fuel

econom y of 27.9 m pg. Adding Daewoo raises GM’s car laboratory value to 28.1 m pg. Adding

Saab and Isuzu does not change the value further. Toyota, Honda, and Hyundai-Kia have the

highest laboratory fuel econom y values, while GM, Fo rd, and DC have the lowest values. DC is

the only m arketing group with over 60 percent truck share, while VW is the only one with less

than 40 percent truck share. Table 29 presents sim ilar data to that in Table 28, except this table

uses adjusted fuel econom y values.

A m o re detailed com p arison of m odel year 2007 laboratory fuel econom y, by vehicle

type and size, is presented in Table 30. St ratifying by m arketing group, vehicle type and size

for MY2007, Toyota has the highest laboratory fuel econom y average in four of the ten classes

in which there is widespread com p etition, Honda leads in three classes, and GM, HK, and VW

each lead in one class. Table 31 is a com p anion table to Table 30, but like Table 29 uses adjusted

m pg data.

Figures 65 through 72 com p are for m odel years 1975 to 2007: percent truck, laboratory

55/45 fuel econom y for cars, trucks, and both cars and trucks for the GM, Ford,

Daim lerChrysler, Toyota, Honda, Hyundai-Kia, Nissan, and VW m a rketing groups, respectively.

For all of these m arketing groups, com b ined car and truck fuel econom y is lower now than it

was in 1988. Because the absolute values of fuel econom y differ som e what across the m a rketing

groups, a separate presentation of the fuel econom y trends was prepared by norm alizing the fuel

econom y for each Group by its fuel econom y in 1988, the year in which fuel econom y for the

fleet as a whole was the highest. In this way, a relative m easure of how each group, com p ared to

its own value in 1988, can be seen. The results are shown in Figures 73 through 80.

All the m a rketing groups have lower absolute fuel econom y now than they did in 1988.

The declines are sim ilar, except the VW Group has not declined as m u ch, due at least in part to

the fact their truck share (shown on Figure 72) has rem ained very low. More inform ation

stratified by m a rketing group can be found in the Appendixes L through O.

68Table 28

**Model Year 2007 Laboratory 55/45 Fuel Economy by Marketing Group**

**<-- FUEL ECONOMY --> Percent** 

**Group Group Member Added**  **Cars Trucks**  **Both Truck** 

GM GM 27.9 21.3 23.8 55%

Above plus Daewoo

Above plus Saab

Above plus Isuzu 28.1

28.1

28.1 21.3

21.3

21.3 24.0

24.0

24.0 53%

53%

53%

Entire GM Group 28.1 21.3 24.0 53%

Ford Ford 26.6 20.7 22.8 59%

Above plus Mazda

Above plus Volvo

Above plus Land Rover

Above plus Jaguar

Above plus Ast. Mart. 27.3

27.3

27.3

27.3

27.2 20.8

20.8

20.6

20.6

20.6 23.4

23.4

23.3

23.3

23.3 54%

52%

53%

53%

53%

Entire Ford Group 27.2 20.6 23.3 53%

DC Chrysler

Above plus Mercedes 25.6

25.1 21.5

21.5 22.8

22.7 66%

61%

Entire DC Group 25.1 21.5 22.7 61%

Toyota Toyota 34.8 24.1 29.0 46%

Honda Honda 33.4 25.0 28.7 48%

Nissan Nissan 31.2 21.2 25.8 44%

HK Kia 33.3 23.9 27.7 52%

Above plus Hyundai 32.3 24.5 28.6 41%

VW VW 28.9 19.7 27.4 11%

Above plus Porsche 28.6 19.7 27.0 13%

Above plus Bentley 28.3 19.7 26.7 13%

Others 27.6 24.7 26.7 27%

All Fleet Average 29.4 22.1 25.3 49%



## 69

### Table 29

**Model Year 2007 Adjusted Composite Fuel Economy by Marketing Group**

**Percent**

**Group**

GM **Group Member Added**

GM

Above plus Daewoo

Above plus Saab

Above plus Isuzu

Entire GM Group **<-- FUEL ECONOMY -->**

**Cars Trucks**  **Both**

22.4 17.2 19.2

22.6 17.2 19.4

22.6 17.2 19.4

22.6 17.2 19.4

22.6 17.2 19.4 **Truck**

55%

53%

53%

53%

51%

Ford

DC Ford

Above plus Volvo Above plus Mazda

Above plus Jaguar Above plus Land Rover

Above plus Ast. Mart.

Entire Ford Group

Chrysler

Above plus Mercedes

Entire DC Group 21.4

21.9 21.9

21.8 21.9

21.8

21.8

20.5

20.1

20.1 16.7

16.7 16.7

16.6 16.6

16.6

16.6

17.3

17.3

17.3 18.3

18.8 18.8

18.7 18.7

18.7

18.7

18.3

18.3

18.3 59%

52% 54%

53% 53%

53%

53%

66%

61%

61%

Toyota Toyota 27.2 19.1 22.8 46%

Honda Honda 26.4 20.0 22.9 48%

Nissan Nissan 24.6 17.0 20.6 44%

HK Kia

Above plus Hyundai 26.2

25.6 19.1

19.5 22.0

22.7 52%

41%

VW VW

Above plus Porsche

Above plus Bentley 23.1

22.9

22.6 15.8

15.9

15.8 21.9

21.6

21.4 11%

13%

13%

Others 22.1 19.7 21.4 27%

All Fleet Average 23.4 17.7 20.2 49%



## 70Table 30

**Model Year 2007 Laboratory 55/45 Fuel Economy by Marketing Group**

VEHICLE

TYPE/SIZE GM Ford DC Toyota Honda Nissan HK VW Others All

Cars

Small 29.5 29.0 27.5 34.0 37.8 25.2 35.4 28.7 28.2 30.3

Midsize 27.2 28.0 27.6 35.1 30.1 32.3 34.8 26.1 26.2 30.8

Large 26.5 24.2 22.8 29.8 23.5 28.6 23.6 22.3 25.3

All 27.8 27.2 25.2 34.3 33.1 31.2 32.4 28.2 27.4 29.3

Wagons

Small 31.5 28.6 27.6 36.4 40.0 29.8 29.0 33.2

Midsize 26.5 28.4 23.0 27.6 28.5 27.8 26.7

Large 22.3 22.3

All 31.5 28.4 24.6 36.4 40.0 27.6 29.0 28.3 30.4

All Cars

Small 29.8 29.0 27.5 35.3 38.0 25.2 35.4 28.7 28.2 30.8

Midsize 27.2 28.0 26.6 35.1 30.1 32.3 34.5 26.7 26.8 30.5

Large 26.5 24.2 22.6 29.8 23.5 28.6 23.6 22.3 25.1

All 28.1 27.2 25.1 34.8 33.4 31.2 32.3 28.3 27.6 29.4

Vans

Small 0.0

Midsize 24.5 24.6 24.6 25.9 24.7 24.4 23.8 24.7

Large 19.7 19.7

All 22.9 24.6 24.6 25.9 24.7 24.4 23.8 24.6

SUVs

Small 20.7 28.6 22.6

Midsize 27.4 25.4 22.0 25.8 25.5 21.4 24.8 23.6 24.6

Large 21.2 19.9 19.3 18.7 21.8 23.1 19.7 23.4 20.8

All 21.6 21.5 21.2 25.2 25.5 21.7 24.7 19.7 24.7 22.6

Pickups

Small 0.0

Midsize 23.4 22.3 24.6 23.7

Large 20.5 18.8 19.2 19.8 21.4 19.6 20.1 19.7

All 20.6 19.3 19.2 21.7 21.4 19.6 20.1 20.1

Fleet

All 24.0 23.3 22.7 29.0 28.7 25.8 28.6 26.7 26.7 25.3



## 71Table 31

**VEHICLE**

**TYPE/SIZE**

**Cars GM**  **Model Year 2007 Adjusted Composite Fuel Economy by Marketing Group**

**Ford DC**  **Toyota Honda**  **Nissan HK**  **VW Others**  **All**

Small

Midsize

Large

All 23.6

22.0

21.5

22.4 23.1

22.4

19.6

21.8 21.8

22.1

18.5

20.3 26.6

27.5

23.8

26.9 29.5

24.0

26.2 20.2

25.4

18.9

24.6 27.7

27.3

23.0

25.6 22.9

21.0

19.0

22.6 22.5

21.1

18.1

22.0 24.0

24.5

20.5

23.4

**Wagons**

Small

Midsize

Large

All 24.8

21.5

24.8 22.9

22.6

22.6 21.8

18.7

18.1

19.7 28.2

28.2 30.7

30.7 22.0

22.0 23.7

22.8

23.2 23.0

22.1

22.4 25.9

21.4

18.1

24.0

**All Cars**

Small

Midsize

Large

All 23.8

22.0

21.5

22.6 23.1

22.4

19.6

21.8 21.8

21.4

18.4

20.1 27.4

27.5

23.8

27.2 29.6

24.0

26.4 20.2

25.4

18.9

24.6 27.7

27.1

23.0

25.6 23.0

21.5

19.0

22.6 22.6

21.5

18.1

22.1 24.4

24.3

20.3

23.4

**Vans**

Small

Midsize

Large

All 19.8

15.8

18.4 19.7

19.7 19.8

19.8 20.6

20.6 20.0

20.0 19.7

19.7 19.2

19.2 0.0

19.9

15.8

19.8

**SUVs**

Small

Midsize

Large

All 21.9

17.2

17.5 20.0

16.2

17.4 16.5

17.7

15.5

17.0 20.3

14.9

19.8 20.3

20.3 17.2

17.5

17.4 19.7

18.7

19.7 15.9

15.9 22.5

18.8

18.8

19.7 17.9

19.5

16.8

18.1

**Pickups**

Small

Midsize

Large

All 18.9

16.4

16.6 17.8

15.2

15.5 15.5

15.5 19.5

15.9

17.3 17.2

17.2 15.8

15.8 16.2

16.2 0.0

18.8

15.8

16.2

**Fleet**

All 19.4 18.7 18.3 22.8 22.9 20.6 22.7 21.4 21.4 20.2



## 72150% 200% 250% 300%

150% 200% 250% 300%

150% 200% 250% 300%

15 0% 20 0% 25 0% 30 0% 

### GM M a r k e t in g Gr o u p For d M a r k e t i ng G r oup



### F ue l E c on om y by M ode l Y e a r Fue l E c onom y by M ode l Y e a r 

### ( T h r ee Y ear M o vi n g A ver ag e) ( T h r ee Y ear M o vi n g A v er ag e)

La bor a t or y 5 5 /4 5 M P G P e r c e nt Tr uc k La bor a t or y 5 5 / 4 5 M P G P e r c e nt Tr uc k

Ca r s

Bo t h

Tr uc k s

P e r c e nt Tr uc k

M ode l Y e a r M ode l Y e a r

F i g u r e 65 F i gur e 6 6 1975 1 980 1985 1990 1995 2000 20 0 5 10 15 20 25 30 35 40

0% 50% 100% Ca r s

Bo t h

T r u cks

P

ercen t T

ru ck

1975 1980 1985 1990 1995 2000 2005 10 15 20 25 30 35 40

0% 50% 100%



### D a i m l e rC h r y s l e r Ma rk e t i n g G r o u p 

### Toy ot a M a r k e t i ng G r oup

Fu e l E c o no m y by M o de l Y e a r 

### Fue l E c onom y b y M ode l Y e a r

( T h r e e Y ear M o vi ng A v e r age) 

### ( T h r ee Y ear M o vi n g A ver ag e)

L ab o ra t o ry 55/ 4 5 M P G P e r c e n t Tr uc k 40 L ab o rat o ry 55/ 45 M P G P e r c e nt Tr uc k

40

35 35

30 30

25 25

100% 20 10 0% 20

50 % 15 50 % 15

0% 10 0% 10

19 75 19 80 19 85 1990 199 5 20 00 20 05 1975 1980 1985 1990 1995 2000 2005

M ode l Y e a r M o d el Y ear

F

i g u re 68

F i gur e 6 7 Ca r s

Bo t h

Tr uc k s

P e rcen t T

ru

ck Ca r s

Bo t h

Tr u c k s

P e r c e nt Tr uc k



## 73150% 200% 250% 300%

150% 200% 250% 300%

150% 200% 250% 300%

15 0 % 20 0 % 25 0 % 30 0 % 

### H onda M a r k e t i ng G r ou p

Fu e l E c onom y b y M ode l Y e a r

( T h r ee Y ear M o vi n g A ver ag e)

L ab o rat o ry 55/ 45 M P G P e r c e nt Tr uc k

40

35

30

25

20 Ca r s

Bo t h

Tr uc k s

P

ercen t T

r u c k 100%

15 50%

10 0%

1975 1 9 8 0 1985 199 0 1995 2000 2005

M ode l Y e a r

F igur e 6 9



### H y unda i

- K i a M a r k e t i n g G r oup

Fue l E c onom y by M ode l Y e a r

( T h r ee Y ear M o vi n g A ver ag e)

L ab o rat o ry 55/ 45 M P G P e r c e nt Tr uc k

40

35

30

25

20 Ca r s

Bo t h

Tr uc k s

P

e r c e nt Tr uc k 100%

15 50 %

10 0%

1975 1980 1985 1990 19 9 5 2000 2005

M ode l Y e a r

F

i g u re 71 

### N i s s an M a r k et i n g G r o u p

F ue l E c o nom y b y M ode l Y e a r

( T h r ee Y e ar M o vi n g A ver a g e)

L a b o r at o r y 55/ 45 M P G P e r c e n t Tr uc k

40

35

30

25

20 Ca r s

Bo t h

Tr uc k s

P e r c e n t Tr uc k 100%

15 50 %

10 0%

1975 1980 1985 1990 1995 2000 2005

Mo d e l Y e a r

F

ig u r e 7 0



### V W M a r k e t i ng G r oup

F ue l E c onom y by M ode l Y e a r

( T h r e e Y ear M o vi n g A ver ag e )

L ab o ra t o ry 55/ 45 M P G P e r c e nt Tr uc k

40

35

30

25

20 10 0 % Ca r s

Tr uc k s Bo t h

Tr uc k s

15 50%

P

e r c e nt Tr uc k

10 0%

19 7 5 1980 1985 1 99 0 1 99 5 2000 2005

M ode l Y e a r

F igur e 7 2



## 74

### N or m a l i z e d F ue l E c onom y N or m a l i z e d Fue l E c onom y

G M M a r k e t i ng G r oup For d M a r k e t i ng G r oup

( T h r ee Y ear M o vi n g A ver ag e) ( T h r ee Y e ar M o vi n g A ver ag e)

Bo t h Ca r s a n d T r u c k s B o t h C ar s an d T r u cks

0. 5 0 0. 7 5 1. 0 0 1. 2 5 N or m a l i z e d F ue l E c onom y ( 1988 = 1. 00)

GM

Al l

0. 5 0 0. 7 5 1. 0 0 1. 2 5 N or m a liz e d F ue l E c onom y ( 1988 = 1

. 00 )

For d

Al l

197 5 198 0 198 5 199 0 1995 2000 2005 1975 1980 198 5 1990 1995 2000 200 5

M o d el Y ear M ode l Y e a r F i g u r e 73 F igur e 7 4



### N or m a l i z ed F u e l E c onom y

D C M a r k e t i ng G r oup

( T h r ee Y ear M o vi n g A v e r ag e)

Bo t h Ca r s a n d T r u c k s

1. 25 N or m a liz e d F ue l E c onom y ( 1988 = 1. 00) 

### N o r m a l i z e d F ue l Ec on om y

T o yo t a M a r ket i n g G r o u p

( T h r ee Y e ar M o v i n g A ver ag e)

1. 25 N or m a liz e d F ue l E c onom y ( 1 988 = 1. 00 ) 

### B ot h C a r s a nd T r uc k s

1. 00 1. 00

0. 75 0. 75

F i g u re 75 1975 1980 0. 50

1985 1990 1995

M ode l Y e a r 20 00 2005

Fi g u r e 7 6 1975 19 80 0. 50

19 85 1990 1995

M ode l Y e a r 20 0 0 20 0 5 DC

Al l To y o t a

Al l



## 75Ho nd a

Al l N i ssa n

Al l

H y unda i

- K i a

Al l VW

Al l 

### N or m a l i z e d Fue l E c onom y

H onda M a r k et i ng G r oup

( T h r ee Y ear M o vi ng A ver ag e)

B o t h C ar s an d T r u cks

1. 25 N or m a liz e d F u e l E c onom y ( 1988 = 1. 00) 1. 25 

### N or m a l i z e d Fue l E c onom y

N i ssan M ar ket i n g G r o u p

( T h r ee Y ear M o vi n g A ver ag e)

N or m a liz e d F ue l E c onom y ( 1 9 8 8 = 1 .0 0 ) 

### B o th C a r s a nd T r u c k s

1. 00 1. 00

0. 75 0. 75

F i g u re 77 1 975 1980 0. 50

1985 1990 1 995

M ode l Y e a r 2000 2005

F i g u re 78 1975 1980 0. 50

1985 1990 199 5

M o d el Y ear 2000 20 0 5

1. 2 5 

### N or m a l i z e d Fu e l E c onom y

H y unda i

- K i a M a r k e t i ng G r oup

( T h r ee Y ear M o vi n g A ver ag e )

N or m a li z e d F ue l E c onom y ( 1 9 8 8 = 1 .0 0 ) 

### Bo t h Ca r s a n d T r u c k s

1. 25 

### N or m a l i z e d Fue l E c onom y

V W M a r k e t i ng G r oup

( T h r ee Y ear M o vi n g A ver ag e)

Bo t h Ca r s a n d T r u c k s

N or m a liz e d F ue l E c onom y ( 1 9 8 8 = 1 .0 0 )

1. 0 0 1. 00

0. 7 5 0. 75

F i g u re 79 1975 1980 0. 5 0

1985 1990 1995

M o d e l Y ear 2000 2005

F i g u re 80 1975 1980 0. 50

1985 1990 199 5

M o d el Y ear 2000 20 0 5



## 76

## VII. Characteristics of Fleets Comprised of Existing Fuel-Efficient Vehicles

This section is lim ited to a discussion of hypothetical fleets of vehicles com p rised of

existing fuel-efficient vehicles and the fuel ec onom y and other characteristics of those fleets.

W h ile it includes a discussion of som e of the tec hnical and engineering factors that affect fleet

fuel econom y, it does not attem p t to evaluate either the benefits or the costs of achieving various

fuel econom y levels. In addition, the analysis presented here also does not attem p t to evaluate

the m arketability or the public acceptance of any of the hypothetical fleets that result from the

scenarios studied and discussed below.

There are several different ways to look at the potential for im proved fuel econom y from

the light-duty vehicle f l eet. Many of these approaches utilize projections of m o re f u el ef f i cient

technologies that are not currently being used in the fleet today. As an exam ple, a fleet m ade up

of a large fraction of fuel cell vehicles could be considered. Such projections can be associated

with a good deal of uncertainty, since uncertainty in the projections of m arket share com pound

with uncertainties about the fuel econom y perform ance of yet uncom m ercialized technology.

These uncertainties can be thought of as a com b ination of technical risk, i.e., can the technology

be developed and m ass produced?

, and m arket risk, i.e., will people buy vehicles with the

im proved fuel econom y?

One general approach used in this report is to consider only the fuel econom y

perform ance of those technologies which exist in today = s fleet. This elim inates uncertainty about

the feasibility and production readiness of the technology and reduces or elim inates the technical

risk but, as m entioned above, does not treat m arket risk. Therefore, the analysis can be thought

of as the fuel econom y potential now in the fleet, with no new technologies added, if the higher

m

pg choices available were to be selected.

As was shown in Figures 3 and 4, there is a wide distribution of fuel econom y. Because

of the interest in the high end of this spectrum , this portion of the database was exam ined in

m o re detail using three A best in class @ (BIC) analysis techniques. This type of technique is not

new, and in fact was one of the m e thods used to investigate future fleet fuel econom y capability

when the original fuel econom y standards were set.

In any group or class of vehicles there will be a distribution of fuel econom y

perform a nce, and the A best in class @ m ethod relies on that fact. The analysis involves dividing

the fleet of vehicles into classes, selecting a set of representative high m pg A role m odel @ vehicles

from each class, and then calculating the average characteristics of the resultant fleet using the

sam e relative sales proportions as in the baseline fleet.

One potential problem with a BIC analysis is that the high m pg cars used in the analysis

m a y be unusual in som e way

Cso unusual that the hypothetical fleet m a de up of them m a y be

deficient in som e other attributes considered desirable by vehicle buyers. Because the BIC

analysis is also sensitive to the selection of the best vehicles, three dif f

erent procedures were

used to select the role m odels.

77

## Two of these selection procedures use the EPA car size classes (which for cars are the

sam e as those used for the EPA/DOE Fuel Economy Guide ) and the truck type/size classes

described previously in this report. The third best-in-class role m odel selection procedure is

based on using the vehicle inertia weight classes used for EPA = s vehicle testing and certification

process.

The advantage of using and analyzing data from the best-in-size class m ethods is that if

the sales proportions of each class are held constant, the sales distribution of the resultant fleet

by vehicle type and size does not change. This m eans that the size of the average vehicle does

not change a lot, but there can be som e fluctuation in interior volum e for cars because of the

distribution of interior volum e within a car class. Sim ilarly, there also is an advantage in using

the inertia weight classes to determ ine the role m odels, since, if the sales proportions in each

inertia weight class are held constant, the sales distribution of the resultant fleet by weight does

not change, and in this case, the average weight rem ains the sam e.

One way of perform i ng a best-in-class analysis is to use as role m odels the four

nam e plates with the highest fuel econom y in each size class. (See Tables Q-1 and Q-2 in

Appendix Q.) Under this procedure, all vehicles in a class with the sam e nam eplate are included

as role m odels regardless of vehicle configuration. Each role m odel nam eplate from each class

was assigned the sam e sales weighting factor, but the original sales weighting distribution for

different vehicle configurations within a give n nam eplate (e.g., transm ission type, engine size,

and/or drive type) was retained. The resulting values were used to recalculate the fleet average

values using the sam e relative proportions in each of the size classes that constitute the fleet. In

cases where two identical vehicles differ by only one characteristic but have slightly different

nam eplates (such as the two-wheel drive Chev rolet C1500 and the four-wheel drive Chevrolet

K1500 pickups), both are considered to have the different nam e plates. Conversely, in the cases

where there are technically identical vehicles w ith different nam e plates (e.g., the Buick LeSabre

and Pontiac Bonneville sedans), only one representative vehicle nam eplate was considered in the

BIC analysis.

The second best-in-class role m odel selection procedure involves selecting as role m odels

the best dozen vehicles in each size class with each vehicle configuration considered separately.

Tables Q-3 and Q-4 in Appendix Q give listings of the representative vehicles used in this

m ethod. As with the previous procedure, in cases where technically identical vehicle

configurations have different nam e plates, onl y one representative vehicle was considered.

Under this best-in-class m ethod, the sales data for each role m odel vehicle in each class was

assigned the sam e value, and the resulting values were used to re-calculate the fleet values again

using the sam e relative proportions in each of the size classes that constitute the fleet.

78

## The third best-in-class procedure involves selecting as role m odels the best dozen

vehicles in each weight class. As with th e previous m ethod, each vehicle configuration was

considered separately. (See Tables Q-5 and Q-6 in Appendix Q for a listing of the vehicles used

in this analysis.) It should be noted that som e of the weight classes have less than a dozen

representative vehicles. In addition, as in the previous two best-in-class m ethods, where

technically identical vehicle configurations with different nam e plates are used, only one

representative vehicle was included. As with the two best-in-size class m ethods, the sales data

for each role m odel vehicle in each class was assigned the sam e value, and the resulting values

were used to recalculate the fleet values again using the sam e relative proportions in each of the

size classes that constitute the f l eet.

Tables 32 to 34 com p are, for cars, trucks, and both cars and trucks, respectively, the

results of the best-in-class analysis with actual average data for m odel year 2007. As discussed

earlier, for the size class scenarios, the percentage of vehicles that are sm all, m i dsize, or large are

the sam e as for the baseline fleet, and in the weight class scenarios, the average weight of the

BIC data sets is the sam e as the actual one.

Under all of the best-in-class scenarios, the vehicles used for the BIC analysis have less

powerful engines, have slower 0-to-60 acceleration tim es, and are m o re likely to be equipped

with front wheel drive, VVT, CVTs, and hybrid power trains than the entire fleet as a whole. For

trucks, the BIC data set vehicles m ake greater use of these sam e technologies plus m u lti-valve

engines.

For both cars and trucks in MY2007, depending on the scenario chosen, cars could have

achieved from 16 to 31 percent better fuel econom y than they did. Sim ilarly, for trucks the fuel

econom y im provem ent ranges from 11 to 23 percent better fuel econom y, and the com b ined car

and truck fleet could have been 12 to 32 percent better.

The best-in-class analyses can be thought of as the m pg potential now in the fleet with no

new technologies added if the higher m pg choices av ailable were selected. As such, the best-in

class analyses provide a useful reference point indicating the variation in fuel econom y levels

that results in large part from consum er preferences as opposed to technological availability.

79Table 32

Best in Class Results 2007 Cars

Vehicle Selection Actual Size Size Weight

Characteristic Basis Data Class Class Class

Selection All Best 4 Best 12 Best 12

Criteria Cars Nameplates Vehicles Vehicles

Fuel Economy Lab. 55/45 29.4 38.5 36.5 34.1

Adjusted City 19.5 25.9 24.4 22.8

Adjusted Highway 27.6 33.5 32.4 30.8

Adjusted Composite 23.4 29.7 28.4 26.7

Vehicle Size Weight (lb.) 3588 3217 3210 3588

Volume (Cu. Ft) 111 111 111 114

Engine CID 176 129 131 155

HP 200 141 146 187

HP/CID 1.16 1.10 1.12 1.20

HP/WT .055 .043 .045 .051

Percent Multivalve 82% 86% 87% 97%

Percent Variable Valve 68% 89% 83% 86%

Percent Diesel 0.1% <0.1% <0.1% 0.4%

Performance 0-60 Time (Sec.) 9.5 10.3 10.4 9.7

Top Speed 138 121 123 133

Ton-MPG 43.2 50.0 47.0 48.8

Cu. Ft. Mpg 2732 3479 3273 3134

Cu. Ft. Ton-MPG 4829 5547 5215 5549

Drive Front 75% 96% 95% 89%

Rear 8% 2% 4% 8%

4WD 17% 2% 2% 3%

Transmission Manual 12% 11% 15% 12%

Lockup 77% 59% 59% 50%

CVT 10% 29% 24% 38%

Hybrid Vehicle 3.0% 28.5% 17.0% 12.6%



## 80Table 33

Best in Class Results 2007 Trucks

Vehicle Selection Actual Size Size Weight

Characteristic Basis Data Class Class Class

Selection All Best 4 Best 12 Best 12

Criteria Trucks Nameplates Vehicles Vehicles

Fuel Economy Lab. 55/45 22.1 27.2 26.0 24.6

Adjusted City 15.1 19.0 17.8 16.7

Adjusted Highway 20.4 23.5 23.4 22.7

Adjusted Composite 17.7 21.3 20.6 19.7

Vehicle Size Weight (lb.) 4723 4164 4087 4723

Engine CID 245 198 195 221

HP 247 195 203 241

HP/CID 1.02 0.99 1.05 1.11

HP/WT .052 .047 .050 .051

Percent Multivalve 58% 61% 72% 69%

Percent Variable Valve 50% 66% 71% 68%

Percent Diesel 0.2% 1.2% 0.5% 1.6%

Performance 0-60 Time (Sec.) 9.7 9.7 9.9 9.8

Top Speed 140 130 133 138

Ton-MPG 42.0 45.4 42.5 46.3

Drive Front 25% 49% 54% 39%

Rear 27% 28% 19% 19%

4WD 49% 24% 28% 42%

Transmission Manual 4% 5% 9% 3%

Lockup 93% 54% 72% 91%

CVT 4% 41% 19% 7%

Hybrid Vehicle 1.4% 30.4% 8.1% 3.8%



## 81Table 34

Best in Class Results 2007 Light Duty Vehicles

Vehicle Selection Actual Size Size Weight

Characteristic Basis Data Class Class Class

Selection All Best 4 Best 12 Best 12

Criteria Vehicles Nameplates Vehicles Vehicles

Fuel Economy Lab. 55/45 25.3 33.4 31.3 28.3

Adjusted City 17.1 22.8 21.2 19.1

Adjusted Highway 23.6 29.0 28.0 25.9

Adjusted Composite 20.2 26.0 24.6 22.5

Vehicle Size Weight (lb.) 4144 3565 3571 4144

Engine CID 210 154 157 190

HP 223 161 169 215

HP/CID 1.10 1.06 1.09 1.15

HP/WT .053 .045 .047 .051

Percent Multivalve 70% 77% 81% 82%

Percent Variable Valve 59% 80% 78% 77%

Percent Diesel 0.1% 0.5% 0.2% 1.0%

Performance 0-60 Time (Sec.) 9.6 10.1 10.2 9.8

Top Speed 139 124 127 135

Ton-MPG 42.6 48.3 45.1 47.5

Drive Front 51% 79% 78% 62%

Rear 22% 12% 10% 14%

4WD 28% 10% 12% 24%

Transmission Manual 8% 9% 13% 7%

Lockup 85% 58% 65% 72%

CVT 7% 33% 22% 22%

Hybrid Vehicle 2.2% 29.2% 13.3% 7.9%



## 82

## Another general approach for determ ining potential fuel econom y im provem ent is to

study the effects on fuel econom y caused by the changes that have occurred in the distributions

of vehicle weight and size. This technique i nvolves preserving the average characteristics of

vehicles within each size or weight strata in today = s fleet, but re-m ixing the sales distributions to

m atch those of a baseline year and then calculating the fleet wide averages for those

characteristics using the re-m ixed sales data. The sales distribution of the resultant fleet by

vehicle type and size, thus is forced to be the sam e as that for the base year. As with the best in

car size class technique, there can be som e fluctuation in average interior volum e for cars

because of the distribution of interior volum e within a car class. Sim ilarly, if the sales

proportions in each inertia weight class are held the sam e as the base year = s, the sales distribution

of the resultant fleet by weight rem ains the sam e as that for the base year change, and the

recalculated average weight is the sam e as the base year = s. In should be noted that both hybrid

and diesel vehicles were excluded from the anal ysis so that only vehicles with conventional

powertrains were considered

Table 35 com p ares laboratory fuel econom y, we ight, interior volum e, engine CID and

HP, estim ated 0-to-60 tim e and fuel econom y for conventionally powered MY2007 cars as

calculated from the actual 2007 sales distribution and then recalculated using the size and weight

distributions from MY1981 and MY1988. The base years of 1981 and 1988 were chosen

because 1981 was the year with the lowest average weight and horsepower levels, and 1988 was

the year with the highest LAB fuel econom y. This table includes the actual 1981 and 1988 fleet

Table 35

**Characteristics of MY 2007 Cars**

**Inertia Interior**  **Engine 0 to 60**  **Lab 55/45**

**Calculated From: Weight**  **Volume CID**  **HP Time**  **MPG**

2007 Actual Distribution 3598 111 178 203 9.4 29.0

1981 Weight Distribution 3043 99 137 168 9.7 32.9

1988 Weight Distribution 3047 103 131 154 10.3 33.9

1981 Size Distribution 3517 108 171 199 9.4 29.4

1988 Size Distribution 3516 108 169 196 9.5 29.3

Reference: 1981 Actual 3043 106 178 99 14.1 24.9

Reference: 1988 Actual 3047 107 160 116 12.8 28.6

**Percent Change:**

2007 Actual Distribution 0% 0% 0% 0% 0% 0%

1981 Weight Distribution -15% -11% -23% -17% 3% 13%

1988 Weight Distribution -15% -7% -26% -24% 10% 17%

1981 Size Distribution -2% -3% -4% -2% 0% 1%

1988 Size Distribution -2% -3% -5% -3% 1% 1%

Reference: 1981 Actual -15% -5% 0% -51% 50% -14%

Reference: 1988 Actual -15% -4% -10% -43% 36% -1%



## 83

## averages as a point of reference. In bot h of the weight distribution cases, the fuel

econom y of the re-m ixed 2007 fleet would have been higher than actually is: 13% if the

1981 weight distribution is used, 17% if the 1988 weight distribution is used. For both

re-m ixed weight cases, interior volum e is sm aller by 11 and 7 percent, respectively, and

horsepower substantially lower. Using the MY1981 and MY1988 size m i x

distributions results in a m u ch sm aller change of only a one percent increase in car fuel

econom y. In addition both of these rem i xed car class scenarios results in an average

weight and horsepower for the hypothetical rem i xed fleets that is very close to the

actual 2007 data.

Table 36 shows sim ilar data for trucks, and as with the car class cases using

either the 1981 or the 1988 sales distribution by weight class, results in higher

recalculated fuel econom y than using the corresponding size class sales distribution.

Figures 81 to 84 com p are actual fuel econom y for all m odel years from 1975 to 2007

with what it would have been had the distributions of weight or size been the sam e as

1981 or 1988. For both cars and trucks, using either the 1981 or 1988 weight class

distribution, results in significantly high fuel econom y im provem ents than the sim ilar

size class cases.

Table 36

**Characteristics of MY 2007 Trucks**

**Inertia Engine**  **0 to 60 Lab 55/45** 

**Calculated From: Weight**  **CID HP**  **Time MPG** 

2007 Actual Distribution 4728 246 248 9.7 22.0

1981 Weight Distribution 3841 180 198 9.9 29.8

1988 Weight Distribution 3838 180 190 10.3 29.1

1981 Size Distribution 4442 246 242 9.8 22.2

1988 Size Distribution 4301 226 223 10.0 23.0

Reference: 1981 Actual 3841 252 121 14.4 19.7

Reference: 1988 Actual 3838 227 141 12.9 21.2

**Percent Change:**

2007 Actual Distribution 0% 0% 0% 0% 0%

1981 Weight Distribution -19% -27% -20% 2% 35%

1988 Weight Distribution -19% -27% -23% 6% 32%

1981 Size Distribution -6% 0% -2% 1% 1%

1988 Size Distribution -9% -8% -10% 3% 5%

Reference: 1981 Actual -19% 2% -51% 48% -10%

Reference: 1988 Actual -19% -8% -43% 33% -4%



## 84

# Effect of W e ight and Si ze On Car Fuel Econom y

Lab 55/45 MPG

40

35

30

25

20

15 Di st r i buti on

Ac t u a l

198 1 We i ght

198 1 Si ze



### 10

1 970 1 975 19 80 19 85 19 90 19 95 200 0 200 5 2010

Model Year

Figur e 81



# Effect of Weight and Si ze On Truck Fuel Economy

40

35

30

25

20

15

10 Lab 55/45 MPG

Di st r i buti on

Ac t u a l

19 81 Wei ght

19 81 Si z e



### 1 970 1 975 19 80 19 85 19 90 19 95 200 0 200 5 2010

Model Year

Figur e 82



## 85

# Effect of W e ight and Si ze On Car Fuel Econom y

Lab 55/45 MPG

40

35

30

25

20

15 Dis tr i but i o n

Ac t u a l

1 9 88 Wei ght

19 8 8 S i ze



### 10

1 970 1 975 19 80 19 85 19 90 19 95 200 0 200 5 2010

Model Year

Figur e 83



# Effect of Weight and Si ze On Truck Fuel Economy

40

35

30

25

20

15

10 Lab 55/45 MPG

Di st r i buti on

Ac t u a l

198 8 We i ght

198 8 Si ze



### 1 970 1 975 19 80 19 85 19 90 19 95 200 0 200 5 2010

Model Year

Figur e 84



## 86

## VIII. References

1. A U.S. Environm ental Protection Agency, Fuel Econom y and Em ission Control, @ Novem ber

1972.

2. "Passenger Car Fuel Econom y - Trends and Influencing Factors," SAE Paper 730790, Austin

and Hellm an, Septem ber 1973.

3. "Fuel Econom y of the 1975 Models," SAE Paper 740970, Austin and Hellm an, October 1974.

4. "Passenger Car Fuel Econom y Trends Through 1976," SAE Paper 750957, Austin and

Service, October 1975.

5. "Light-Duty Autom otive Fuel Econom y Trends Through 1977," SAE Paper 760795, Murrell,

Pace, Service, and Yeager, October 1976.

6. "Light-Duty Autom otive Fuel Econom y Trends Through 1978," SAE Paper 780036, Murrell,

February 1978.

7. "Light-Duty Autom otive Fuel Econom y Trends Through 1979," SAE Paper 790225, Murrell,

February 1979.

8. "Light-Duty Autom otive Fuel Econom y Trends Through 1980," SAE Paper 800853, Murrell,

Foster and Bristor, June 1980.

9. "Light-Duty Autom otive Fuel Econom y Trends Through 1981," SAE Paper 810386, Foster,

Murrell and Loos, February 1981.

10. "Light-Duty Autom otive Fuel Econom y Trends Through 1982," SAE Paper 820300, Cheng,

LeBaron, Murrell, and Loos, February 1982.

11. A W hy Vehicles Don' t Achieve EPA MPG On the Road and How That Shortfall Can Be

Accounted For," SAE Paper 820791, Hellm an and Murrell, June 1982.

12. A Light-Duty Autom obile Fuel Econom y Trends through 1983," SAE Paper 830544, Murrell,

Loos, Heavenrich, and Cheng, February 1983.

13. "Passenger Car Fuel Econom y - Trends Through 1984," SAE Paper 840499, Heavenrich,

Murrell, Cheng, and Loos, February 1984.

14. "Light Truck Fuel Econom y - Trends through 1984," SAE Paper 841405, Loos, Cheng,

Murrell and Heavenrich, October 1984.

87

## 15. "Light-Duty Autom otive Fuel Econom y - Trends Through 1985," SAE Paper 850550,

Heavenrich, Murrell, Cheng, and Loos, March 1985.

16. "Light-Duty Autom otive Trends Through 1986," SAE Paper 860366, Heavenrich, Cheng,

and Murrell, February 1986.

17. "Trends in Alternate Measures of Vehicle Fuel Econom y," SAE Paper 861426, Hellm an and

Murrell, Septem ber 1986.

18. "Light-Duty Autom otive Trends Through 1987," SAE Paper 871088, Heavenrich, Murrell,

and Cheng, May 1987.

19. "Light-Duty Autom o tive Trends Thr ough 1988," U.S. EPA, EPA/AA/CTAB/88-07,

Heavenrich and Murrell, June 1988.

20. "Light-Duty Autom otive and Technology Trends Through 1989," U.S. EPA,

EPA/AA/CTAB/89-04, Heavenrich, Murrell, and Hellm an, May 1989.

21. "Downward Trend in Passenger Car Fuel Econom y--A View of Recent Data," U.S. EPA,

EPA/AA/CTAB/90-01, Murrell and Heavenrich, January 1990.

22. "Options for Controlling the Global W a rm ing Im pact from Motor Vehicles," U.S. EPA,

EPA/AA/CTAB/89-08, Heavenrich, Murrell, and Hellm an, Decem ber 1989.

23. "Light-Duty Autom otive Technology and Fuel Econom y Trends Through 1990," U.S. EPA,

EPA/AA/CTAB/90-03, Heavenrich and Murrell, June 1990.

24. "Light-Duty Autom otive Technology and Fuel Econom y Trends Through 1991," U.S.

EPA/AA/CTAB/91-02, Heavenrich, Murrell, and Hellm an, May 1991.

25. "Light-Duty Autom otive Technology and Fuel Econom y Trends Through 1993," U.S.

EPA/AA/TDG/93-01, Murrell, Hellm an, and Heavenrich, May 1993.

26. "Light-Duty Autom otive Technology and Fuel Econom y Trends Through 1996," U.S.

EPA/AA/TDSG/96-01, Heavenrich and Hellm an, July 1996.

27. "Light-Duty Autom otive Technology and Fuel Econom y Trends Through 1999," U.S..

EPA420-R-99-018, Heavenrich and Hellm an, Septem ber 1999.

28. "Light-Duty Autom otive Technology and Fuel Econom y Trends 1975 Through 2000," U.S.

EPA420-R-00-008, Heavenrich and Hellm an, Decem ber 2000.

88

## 29. "Light-Duty Autom otive Technology and Fuel Econom y Trends 1975 Through 2001," U.S.

EPA420-R-01-008, Heavenrich and Hellm an, Septem ber 2001.

30. "Light-Duty Autom otive Technology and Fuel Econom y Trends 1975 Through 2003," U.S.

EPA420-R-03-006, Heavenrich and Hellm an, April 2003.

31. "Light-Duty Autom otive Technology and Fuel Econom y Trends 1975 Through 2004," U.S.

EPA420-R-04-001, Heavenrich and Hellm an, April 2004.

32. "Light-Duty Autom otive Technology and Fuel Econom y Trends 1975 Through 2005,” U.S.

EPA420-R-05-001, Robert M. Heavenrich, July 2005.

33. “Light-Duty Autom otive Technology and Fuel Econom y Trends 1975 Through 2006,” U.S.

EPA420-R-06-011, Robert M. Heavenrich, July 2006.

34. A Concise Description of Auto Fuel Econom y in Recent Years," SAE Paper 760045,

Malliaris, Hsia and Gould, February 1976.

35. A Autom o tive Engine

B A Future Perspective @ , SAE Paper 891666, Am ann, 1989.

36. A Regression Analysis of Acceleration Perform a nce of Light-Duty Vehicles, @ DOT HS 807

763, Young, Septem ber 1991.

37. A Determ inates of Multiple Measures of Acceleration, @ SAE Paper 931805, Santini and

Anderson, 1993.

89