Current Corporate Average Fuel Economy (CAFE) standards require carmakers to achieve a fleet average of 54.5 mpg by 2025.

That standard, which equates to about 40 mpg on new-vehicle window stickers, is the backbone of U.S. policy to reduce carbon emissions from cars and trucks.

It has also been seen as a daunting technical challenge for carmakers—but one, it turns out, that they're largely meeting.

DON'T MISS: Gas Mileage Rules For 2025 Could Be Lowered If Buyers Stick With SUVs (Mar 2015)

For the second year in a row, more than half of new passenger car and truck models sold in the U.S. meet or beat efficiency targets for their categories, according to a study (PDF) issued yesterday by the Consumer Federation of America.

The news should bode well for an upcoming midterm review of the 2019-2025 standards that will take place over the next couple of years.

Of almost 1,100 vehicles from the 2016 model year surveyed, 56 percent met or exceeded fuel-efficiency targets for their class of vehicle.

2016 Chevrolet Cruze

2016 Chevrolet Cruze

Models that achieved more than 30 mpg comprised 13.4 percent of the fleet, compared to 11.7 percent for 2015 and just 1.0 percent in 2008.

At the same time, the number of gas guzzlers has decreased.

Vehicles rated at less than 16 mpg made up 4.0 percent of the fleet, down from 6.1 percent in 2015 and 32.2 percent in 2008.

ALSO SEE: Auto Industry Doing Fine In Meeting Gas-Mileage Goals, It Turns Out (Aug 2014)

Researchers paid more attention to models that were redesigned or substantially updated for 2016, as they are likely to remain on sale for several years with few changes.

Among that group, 63 percent of models were found to meet or exceed efficiency targets.

For example, the 2016 Chevrolet Malibu Hybrid, Chevrolet Cruze, and Toyota RAV4 are expected to be compliant until 2024, the CFA says.

2016 Toyota RAV4 SE

2016 Toyota RAV4 SE

So will the 2016 Chevy Volt and Toyota Prius, each of which was completely redesigned for the current model year.

The Ford F-150 full-size pickup truck redesigned last year should remain compliant until 2021, the CFA says.

But those fuel-efficient cars won't make much of an impact if no one buys them.

MORE: Fuel-Economy Rules Likely To Stay Put Through Midterm Review: Consensus (Dec 2014)

Despite today's relatively low gas prices, CFA researchers found that consumers still consider fuel economy to be important.

In a March 2016 survey, 81 percent of respondents said fuel economy would be an "important" consideration when buying a new car, and 54 percent said it would be "very important."

Regarding CAFE standards, 81 percent said they supported the rules, and 52 percent said they strongly supported them.

2016 Ford F-150 Limited

2016 Ford F-150 Limited

Last year's low gas prices caused a spike in SUV sales, however, while sales of plug-in electric cars remained essentially flat.

The U.S. Environmental Protection Agency has hinted that this change in the mix of new-vehicle sales might force it to consider changes to CAFE rules.

Still, and despite some protests from carmakers, the general consensus within the industry seems to be that CAFE rules will remain unchanged through 2025.


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