Ford F-150 Ecoboost
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Data compiled by TrueCar shows that, despite gasoline costing some $3.71 a gallon in the U.S., there was no more of a rush to purchase fuel-efficient vehicles in July than there was in June, when gas averaged a slightly more reasonable $3.59.

TrueCar says that U.S. consumers stemmed a three-month slide in fuel efficiency in July by purchasing vehicles that averaged 21.6 miles per gallon, identical to the results posted in June.

Why does bumping up that 21.6 mpg number even matter? Well, TrueCar estimates that an increase of just one mpg on the estimated annual U.S. sales of approximately 13 million vehicles would reduce fuel consumption by a whopping 416 million gallons. So, yeah, every single mpg matters.
Related Gallery2011 Ford F-150 EcoBoost