The U.S. Environmental Protection Agency has released its annual report, "Light-Duty Automotive Technology and Fuel Economy Trends: 1975 Through 2005," which provides data on the fuel economy and performance characteristics of cars, vans, sports utility vehicles and pickup trucks for model years 1975 through 2005. Fuel economy has been relatively constant since 1997, according to the report, ranging from 20.6 to 21.0 miles per gallon (mpg).

Model year 2005 vehicles are estimated to average 21.0 mpg, 0.2 mpg higher than 2004, but 5% below the fleet-average fuel economy peak value of 22.1 mpg achieved in 1987. The EPA attributed the increase largely to higher fuel economy standards for light trucks and SUVs implemented in 2005, but said that improvement was partly offset by the increasing popularity of less fuel-efficient light trucks, particularly SUVs.

While fuel economy levels have been relatively constant, vehicle performance and weight have increased, according to the EPA report, which concludes that recent technology developments such as hybrid-electric vehicles, clean diesel technology and variable displacement engines hold promise for the near-term future. The report can be found at: http://www.epa.gov/otaq/fetrends.htm.