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Fuel Station
Fuel Station
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Americans have been enjoying uncharacteristically low gas prices for nearly two years, but many of us are still burning money every time we step on the gas.

Drivers have acclimated to today's low gas prices all too well: It's gotten to the point where, even though we were elated when prices fell below $3 per gallon in October of 2014, there was consternation when it failed to continue its slide below $2 per gallon several months later.

But with prices still hovering in that just-over-$2 range (the most recent data shows that the national average was $2.21 per gallon, according to AAA), perhaps it's to be expected that we'd get a little cavalier with our spending at the gas pump.

Here's how it plays out: We waste roughly $2.1 billion per year on premium gas. While some car manufacturers recommend premium gasoline for certain high-performance models, AAA found that 16.5 million drivers who have cars for which premium gas is not recommended still filled up with the pricier fuel over the past 12 months. And most of those buying expensive gas did so at least once a month.

That's a total of 270 million trips to the gas station that cost Americans more than they should have, even with gas prices as low as they are today. (Regular gas is 87-octane while premium is 93-octane, and experts say that's the only difference; "premium" doesn't signify a difference in quality.)

AAA found that roughly 70% of cars on the road in the U.S. today take regular gas, 16% call for premium and the remainder either recommend mid-grade or use an alternative source of energy.

If your owner's manual calls for regular gas, you're just wasting money, the AAA's Megan McKernan, manager of the Automobile Club of Southern California’s Automotive Research Center, said in a statement.

"There is no benefit to using premium gasoline in a vehicle that requires regular fuel,” she said. “Premium gasoline is specifically formulated to be compatible with specific types of engine designs and most vehicles cannot take advantage of the higher octane rating.”