America's cars, trucks and SUVs took a record step in 2012 toward a cleaner future, with the average fuel economy for new vehicles hitting an all-time high of 23.6 miles per gallon, according to a new report released by the Environmental Protection Agency.

That average is a 1.2 mpg increase compared with 2011, a jump that is the second-highest in the past 30 years. Fuel economy has increased in seven of the past eight years, the agency announced in Thursday's report.

"Today's new vehicles are cleaner and more fuel efficient than ever, saving American families money at the gas pump and helping to keep the air that we breathe cleaner," Janet McCabe, acting assistant administrator for EPA's Office of Air and Radiation, said in a statement. "Each year, new technologies are coming online to keep driving these positive trends toward greater and greater efficiency."

Among the individual brands, Mazda, Honda and Volkswagen Group occupied the top three spots in terms of overall fuel economy for 2012, at 27.1 mpg, 26.6 mpg and 25.8 mpg, respectively.

GM, Daimler (parent company of Mercedes-Benz) and Chrysler Group had the lowest averages among all automakers, with averages of 21.7 mpg, 21.1 mpg and 20.1 mpg respectively.

Since 2004, fuel economy averages are up 4.3 mpg, or 22 percent. Early data show that further gains are expected for vehicles from the 2013 model year, though they'll be smaller than what was announced in Thursday's report.

"This is a big deal," Dan Becker, director of the Safe Climate Campaign, said in a statement. "It's a big down payment on a better future. One year ago the Obama administration put tough standards into effect to protect the climate. Now we see that the auto companies are meeting those standards — and making money selling cleaner cars."