According to the American School Bus Council, the average fuel consumption for diesel-powered buses is seven miles per gallon.

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In June, diesel exports reached a record high of nearly 20 million barrels, or more than 20% of the average U.S. monthly diesel fuel consumption--97.6 million barrels per month in 2006.

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Even as the average car's fuel efficiency has risen 58% since then, U.S. oil consumption has risen 19% to 19.5 million barrels a day.

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