You might be forgiven for thinking that as cars get ever heavier, better equipped, safer, more practical, more powerful and faster, fuel economy would suffer.

Thankfully, the EPA's latest set of statistics proves that isn't the case--and dispels other notions such as increasing weight and ever greater power figures, too.

The U.S. Environmental Protection Agency has just released its full set of statistics for 2012 model year cars and trucks, which have now hit a record 23.6 mpg on average.

No, that's not a lot altogether. But when you consider how many large trucks make up U.S. sales, it's a sign that both regular vehicles are getting ever more efficient, and that trucks themselves are improving enough to allow that average to rise overall, rather than remain constant.

That figure represents a whole 1.2 mpg improvement over the 2011 model year--the second highest improvement in the last 30 years, according to The Detroit News. And when statistics for the 2013 model year land, the overall average could top 24 mpg--another record. Since 2004, economy has risen by 4.3 mpg, or 22 percent.

Some individual manufacturers, unburdened by big trucks and gas-guzzling sports cars, scored significantly above the overall average.

Mazda was highest overall, with a fleet-wide 2012 economy figure of 27.1 mpg, itself a full 2.1 mpg higher than in 2011. Predictably, Japanese automakers rounded out the top three, with Honda on 26.6 mpg and Toyota at 25.6 mpg.

Volkswagen is next on 25.8 mpg, though this fell 0.2 mpg compared to 2011. Hyundai and Kia, whose mileage was investigated by the EPA, aren't listed.

Ford is the highest-placed U.S. automaker on 22.8 mpg for 2012, a boost of 1.7 mpg on 2011. That said, Ford is expected to fall 0.2 mpg for 2013. GM is next on 21.7 mpg, and the small number of Fiat 500s sold in the U.S. hasn't been enough to offset Chrysler's 20.1 mpg average--though this could jump by 1.5 mpg in 2013.

Despite these general improvements, the EPA reports that performance hasn't suffered. The average car still reaches 60 mph from rest in 9.4 seconds, unchanged from 2011's numbers.

That's even more impressive considering average power actually fell by 8 horsepower to 222 hp in 2012. But perhaps it's not unexpected, either--average weight fell by a full 150 pounds from 2011 to 2012.

Most of these changes, the EPA reports, are due to a decrease in light truck market share from 2011 to 2012. And in 2013, weight and power may increase again, though this won't be known for sure until 2013's report.

The bottom line is that despite safety and equipment advancements, our cars are getting more efficient--and we're not sacrificing performance to do so.


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