Automakers continued to beat U.S. fuel-efficiency standards in 2015 model vehicles, putting the industry on track to reach an average 50 miles per gallon by 2025.

The latest snapshot of the industry’s technological progress was released today by the U.S. Environmental Protection Agency.

Every major automaker is in compliance with the federal fuel-economy standards. But four of them—Fiat Chrysler, Kia, Mercedes and VW—needed to dip into their stockpile of fuel-economy credits from previous model years to meet their targets.

Mazda delivered the best overall fuel economy, followed by Honda and Nissan.

"Even as fuel economy standards are tightening and gas prices remain low, automakers are rising to the challenge," said Shannon Baker-Branstetter, energy policy counsel for Consumers Union, the policy and mobilization arm of Consumer Reports. "This new report shows that automakers can do even more to improve efficiency in every vehicle segment."

Automakers have beaten fuel-economy standards every year since the targets started ramping up in the 2012 model year, but the gap is narrowing.

The latest report covers model year 2015, and the industry as a whole beat its target by 2.5 percent. In 2014, the industry exceeded the regulatory goal by 4.5 percent.

Overall, fuel economy has improved by 28 percent since 2004, from less than 20 mpg to 24.8 mpg, the EPA said. Consumers are saving fuel even as more of them are buying light trucks rather than cars.

Car fuel economy reached an average 29.4 mpg in 2015 models, an all-time high, though car sales represented a record low 47 percent of all vehicle sales. Sport utility vehicle sales accounted for 38 percent of sales, the highest ever.

Because of the growing popularity of larger vehicles, automakers have argued that regulators should revise the standards to reflect that. Each vehicle category, such as SUV or pickup truck, has its own fuel-economy targets. But the industry is still concerned that overall targets, which are rising every year, won’t be met because of consumer preferences.

Many of the consumers shifting into SUVs are buying models built on car platforms. Car-based SUVs increased to 25.3 mpg, better than the 24.8 mpg average for the entire fleet. Truck-based SUVs are also getting more efficient, to 22.0 mpg.

"It's especially encouraging to see that larger vehicles are improving the fastest," Baker-Branstetter said.