U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2005—3144

January 2006

Steel Stocks in Use in Automobiles in the United States

The U.S. Geological Survey estimated the quantity of steel 

stocks in use in the United States to be 4.13 billion metric tons as of 

2002 (Sullivan, 2005). Stocks in use include the steel in airplanes, 

automobiles, bridges, buildings, household appliances, machinery, 

and many other applications and exclude steel in solid-waste facilities. Continuous use of steel through recycling, remanufacturing, 

and reuse allows stocks in use to be considered a resource in place. 

The term “steel” is used here to denote carbon steel, galvanized 

steel, stainless steel, and high-strength low-alloy steel (HSLA), as 

well as cast iron and iron. 

Automobiles are made from a great variety of materials, 

including steel, aluminum, copper, and plastics. Steel is still the 

largest component by weight used in an automobile, accounting for 

more than 60 percent of an average automobile’s weight (table 1). 

Automakers consider steel a cost-effective material that is highly 

formable, at the same time maintaining its durability, high strength, 

and stiffness (Ashley, 1997).

Between 95 and 100 percent of the steel used in automobiles 

can be recycled or reused as reclaimed parts (American Metal 

Market, 1993, p. 13A–14A; 1994, p. 6; Great Lakes Institute for 

Recycling Markets, 1998, p. 10). Steel used in automobile bodies 

is made with about 25 percent recycled steel, whereas internal steel 

parts are made with a higher percentage of recycled steel (Steel 

Recycling Institute, 2005).

This Fact Sheet compares all steel stocks in use with steel 

stocks in use within automobiles in the United States. Automobiles 

in use in the United States include domestic and imported passenger cars, sport utility vehicles (SUVs), trucks, light trucks, vans, 

and minivans in commercial (taxicabs and limousines), government, and private use. Data on vehicles with an average vehicle 

curb weight greater than 8,500 pounds are not included in the Fact 

Sheet. The curb weight (CW) is the total weight of a vehicle without passengers or cargo.

During the past 30 to 35 years, the use of steel in automobiles 

has decreased in terms of (1) the average amount by weight used 

per vehicle and (2) steel’s percentage of the average vehicle curb 

weight (table 1). In model year 1970, steel made up about 87.3 

percent of the average automobile’s CW. This percentage dropped 

to about 78.4 percent by model year 1985, to about 68.4 percent by 

2000, and to about 66.4 percent in 2004. The decline in steel usage 

by weight per vehicle of about 32 percent between model years 

1970 and 2004 was due largely to downsizing of the automobile 

and substitution (1) of aluminum, magnesium, and plastics for steel 

body parts and (2) of aluminum for cast iron in cylinder heads, 

engine blocks, and rear-axle and transmission housings. 

From 1970 through 2001, the number of automobiles in use 

increased by more than 120 percent, and the estimated average 

steel content per vehicle in use decreased by about 28 percent (table 2). 

In 1970, the average steel content per vehicle in use was 3,050 

pounds, 98.1 million vehicles were in use, and the steel stocks in 

use within automobiles in the United States were about 136 million 

metric tons (136 Mt), which were 6.2 percent of all steel stocks in 

use (2,210 Mt). At the end of the 31-year period, 217 million automobiles were in use, but the average steel content per vehicle in use 

had decreased to 2,210 pounds. Therefore, the percentage of steel 

stocks in use within automobiles in the United States decreased to 

about 5.3 percent of all steel stocks in use (4,070 Mt). 

Steel contained within all stocks in use increased at a rate 

of about 2.0 percent per year, whereas steel stocks contained in 

automobiles in use increased at a rate of about 1.5 percent per year 

from 1970 to 2001. It would appear that the decreased use of steel 

per vehicle was offset by the increase in the number of automobiles 

in use and that all steel stocks in use increased, but not as a result of 

steel’s use in automobiles (fig. 1). 

By the mid-1960s, concerns about automobile safety 

(National Traffic and Motor Vehicle Safety Act and Highway 

Safety Act, both enacted in 1966) initially increased the use of 

steel in automobiles. The estimated average content of steel in 

automobiles in the mid-1960s was 3,000 pounds per vehicle (table 

2). By 1975, the average steel content of automobiles in use had 

increased to 3,160 pounds per vehicle (table 2). Concerns about 

automobile exhaust emissions and fuel efficiency led to emission 

controls (Clean Air Act, enacted in 1970) and increased mileageper-gallon standards expressed as corporate average fuel economy 

(CAFE) standards (Energy Policy Conservation Act, enacted in 

1975). First established in 1978, fuel-efficiency requirements have 

been changed since then in 1979, 1980, 1981, 1985, 1986, and 

1990 (National Highway Traffic Safety Administration, 2005a). 

As CAFE and emission laws became more stringent in the late 

1970s through the mid-1980s, automakers needed to improve fuel 

economy. This goal was achieved in part by reducing the weight of 

the automobile by changing construction design and by substituting 

lighter weight metals and plastics for steel.

In 1980, the average steel content per automobile in use 

was about 2,950 pounds. By 1990, the average steel content per 

automobile had decreased to 2,410 pounds. However because of a 

Table 1. Steel content of automobiles built in the United States, averaged for selected model years.

[CW, curb weight of automobile. Sources: Ward’s Communication, 1977, p. 65; 1982, p. 21; 1985, p. 21; 1987, p. 30; 1989, p. 37; 1990, p. 73; 2002, p. 37; J.F. Lemons, 

Jr., U.S. Bureau of Mines, written commun., 1989; D.A. Kramer, U.S. Geological Survey, oral and written commun., January 25, 2005; National Highway Traffic Safety 

Administration, 2005b]

Auto weight and steel content Model year

1970 1975 1980 1985 1990 1995 2000 2001 2004

Average CW, in pounds....................................... 3,620 3,730 2,870 2,870 2,910 3,050 3,130 3,150 3,240

Average steel content per vehicle, in pounds...... 3,160 2,830 2,460 2,250 2,170 2,170 2,140 2,130 2,150

Average steel content per vehicle as a

percentage of average CW................................ 87.3 75.9 85.7 78.4 74.6 71.1 68.4 67.6 66.4
28 percent increase in the number of automobiles in use from 1980 

to 1990, steel stocks in use in automobiles increased by about 5 

percent. 

Through the 1990s, demand increased for larger vehicles such 

as vans, SUVs, light trucks, and trucks; use of these larger vehicles 

led to an 11 percent increase in steel stocks in use in automobiles 

by 2001. Steel stocks in use in automobiles amounted to about 198 

Mt, 5.4 percent of steel contained within all stocks in use in 1995. 

By 2001, steel stocks in use in automobiles reached 217 Mt, 5.3 

percent of steel contained within all stocks in use. 

If the popularity of larger vehicles continues, automobile 

manufacturers will need to keep weight increases to a minimum 

in order to meet emissions and fuel-efficiency requirements. The 

increased use of light-weight metals and materials such as aluminum, magnesium, and plastics in automobiles is expected to 

continue; with substitution of these materials where possible, the 

amount of steel used per vehicle may continue to decline. With 

more automobiles in use, steel stocks in use contained in automobiles are expected to remain flat or slightly increase.

By David A. Buckingham

References Cited

American Metal Market, 1993, Steel Monthly—Electric furnace steel: February 

18, p. 13A–14A.

American Metal Market, 1994, Steel-funded study knocks aluminum in cars: 

April 28, p. 6.

Ashley, S., 1997, Steel cars face a weighty decision: Mechanical Engineering, v. 

119, no. 2 (February 1997), p. 56–62. 

Davis, S.C., 1997, Transportation energy data book; Edition 17: Oak Ridge, 

Tenn., Oak Ridge National Laboratory, Center for Transportation Analysis, 

Energy Division, 280 p., available online at http://www.ntl.bts.gov/lib/5000/

5800/5844/17th_edition/tedb17.pdf. (Accessed May 23, 2005.)

Davis, S.C., and Diegel, S.W., 2004, Transportation energy data book; 

Edition 24: Oak Ridge, Tenn., Oak Ridge National Laboratory, Center for 

Transportation Analysis, Engineering Science & Technology Division, 

348 p., available online at http://cta.ornl.gov/data/index.shtml. (Accessed 

December 5, 2005.)

Great Lakes Institute for Recycling Markets, 1998, Auto recycling 

demonstration project: Ann Arbor, Mich., 132 p., available online at http://

www.deq.state.mi.us/documents/deq-ead-recycle-autofinal.pdf. (Accessed 

May 17, 2005.)

1970 1975 1980 1985 1990 1995

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

STEEL STOCKS IN USE, IN 

MILLIONS OF METRIC TONS

4,500

4,000

3,500

3,000

2,500

2,000

1,500

1,000

500

0

AVERAGE VEHICLE CURB

WEIGHT, IN POUNDS

2001

2000

Vehicle curb weight

Total steel

stocks in use

Steel stocks contained in 

non-automotive uses

Steel stocks contained in automobiles in use

YEAR

National Highway Traffic Safety Administration, 2005a, CAFE overview—Frequently asked questions: available online at http://www.nhtsa.dot.gov/cars/

rules/CAFE/overview.htm. (Accessed April 29, 2005.)

National Highway Traffic Safety Administration, 2005b, New passenger car 

fleet average characteristics and Historical passenger car fleet average 

characteristics: available online at http://www.nhtsa.gov/cars/rules/CAFE/

NewPassengerCarfleet.htm and http://www.nhtsa.gov/cars/rules/CAFE/

HistoricalCarfleet.htm. (Accessed December 5, 2005.)

Steel Recycling Institute, 2005, Recycling scrapped automobiles: Pittsburgh, 

Pa., 1 p., available online at http://www.recycle-steel.org/pdfs/brochures/

auto.pdf. (Accessed May 17, 2005.) 

Sullivan, D.E., 2005, Metal stocks in use in the United States: U.S. Geological Survey Fact Sheet 2005–3090, 2 p., available online at http://pubs.usgs.

gov/fs/2005/3090. (Accessed December 5, 2005.)

Ward’s Communication, 1977–2002 (selected years), Ward’s automotive yearbook: Southfield, Mich., 1977, 382 p.; 1982, 247 p.; 1985, 242 p.; 1987, 264 

p.; 1989, 304 p.; 1990, 304 p.; 2002, 350 p. 

For more information, please contact:

David A. Buckingham, U.S. Geological Survey

Denver Federal Center, Box 25046, MS 750

Denver, CO 80225–0046

Telephone: 303–236–8747, ext. 239

E-mail: buckingh@usgs.gov

Table 2. Automobiles in use and steel stocks in use in automobiles and all applications in the United States, averaged for selected years.

[Mt, million metric tons; each metric ton equals 2,204.6 pounds. Sources: Ward’s Communication, 1977, p. 65; 1982, p. 21, 212; 1985, p. 21; 1987, p. 30, 147; 1989, p. 

37; 1990, p. 73; 2002, p. 277; J.F. Lemons, Jr., U.S. Bureau of Mines, written commun., 1989; Davis, 1997, p. 3–7; Davis and Diegel, 2004, p. 3–5; Sullivan, 2005; D.A. 

Kramer, U.S. Geological Survey, oral and written commun., January 25, 2005; The Polk Company, oral commun., April 4, 2005]

Autos and steel stocks

Calendar year

Mid1960s 1970 1975 1980 1985 1990 1995 2000 2001

Automobiles in use, in millions of units..... 90.6 98.1 120 140 157 179 193 213 217

Average steel content per vehicle in use, 

in pounds................................................... 3,000 3,050 3,160 2,950 2,680 2,410 2,260 2,220 2,210

Steel stocks contained within automobiles 

in use, in Mt.............................................. 125 136 172 187 191 196 198 214 217

All steel stocks in use, in Mt....................... 1,702 2,210 2,570 2,920 3,180 3,410 3,660 4,010 4,070

Steel stocks contained within automobiles 

in use, as a percentage of all steel stocks 

in use......................................................... 7.3 6.2 6.7 6.4 6.0 5.7 5.4 5.3 5.3

Figure 1. Comparison of steel stocks in use contained in 

automobiles in use with all steel stocks in use and the average 

vehicle curb weight in the United States for the years 1970 through 

2001. Sources as in tables 1 and 2.