WASHINGTON (Bloomberg) -- The U.S. may require annual fuel- efficiency improvements of 2 percent to 7 percent from 2017 to 2025 for cars and light trucks, according to the National Highway Traffic Safety Administration.
The agency said in a May 10 Federal Register notice it will evaluate the costs and environmental effects of boosting fuel efficiency in the proposed rule it's scheduled to publish in September.
Automakers must have a fleet-wide average of 34.1 miles per gallon, according to the existing fuel-economy rule that applies through model-year 2016 vehicles. NHTSA is developing the next rule with the Environmental Protection Agency and California's Air Resources Board.
The U.S. said last year automakers selling cars in the U.S. may be required to almost double fuel economy to as much as 62 miles per gallon by 2025 models with annual fuel-economy increases of as much as 6 percent.