DETROIT -— Automakers are making slow but steady progress improving fuel efficiency, as the industry hit a high for the average miles per gallon of new vehicles sold in August in the United States.
A study released by the University of Michigan on Tuesday said that the average fuel economy on the window stickers of cars and trucks sold last month was 24.9 miles per gallon. That's nearly 5 miles per gallon better than the 20.1 mpg recorded in October 2007, when the university's Transportation Research Institute began tracking the data.
The improvements reflect broad changes across the industry in the size, weight and engines in new models, as well as an increase in the number of hybrid and electric vehicles on the market.
"Consumers are interested in fuel-efficient vehicles, and automakers can make them," said Don Anair, a green-car expert with the Union of Concerned Scientists.
The car companies are under pressure to increase fuel efficiency to meet strict federal standards for corporate average fuel economy, or CAFE.
But the latest data indicate that automakers are apparently on track to at least meet interim goals agreed to last year in negotiations with the Obama administration.
The CAFE performance of a vehicle is several miles per gallon better than the fuel economy numbers on window stickers of new vehicles in the showroom. Last month, the university's research showed that for CAFE purposes, new vehicles achieved 30.1 mpg, not including credits and adjustments that manufacturers are allowed under the federal rules.
Under the new government standards, automakers have agreed to a fleetwide CAFE mandate of 35.5 mpg by 2016 and 54.5 mpg by 2025.
Anair said that 35.5 mpg under the CAFE formula was equivalent to about 27 mpg listed on a window sticker. That would make the 2016 goal achievable at the current rate of improvement.
The overall gains in fuel economy since 2007 have accelerated since the U.S. automakers have recovered from the recession.
General Motors and Chrysler both went bankrupt four years ago and needed government bailouts to stay in business. Since then, they have brought out some of their most fuel-efficient models.
Ford, the only Detroit car company to avoid bankruptcy, has also made rapid improvement in the fuel economy of its cars and pickups.