Falling ethanol prices should also help. Ethanol accounts for about 10 percent of the total volume of blended gasoline. Kloza figures the temporary spike in cost of ethanol—which has since eased—added between 5 to 12 cents a gallon prices to the price at the pump
And crude oil remains relatively cheap and plentiful—especially for Gulf coast refiners. Last month, inventories hit a record 207 million barrels, according to the Energy Information Administration.
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The glut resulted from continued increases in U.S. crude production which is now flowing in greater volume to the Gulf through the southern portion of the Keystone pipeline, which opened earlier this year. Refiners also have been using less crude as they've slowed production to run through their annual maintenance drills.
Those refiners are also seeing U.S. demand for gasoline continue a gradual decline—after peaking in 2007. While gasoline consumption continues to rise during summer driving season and fall during the winter, several forces continue to drive the long-term trend to falling demand for gasoline, according to Kloza.
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"You don't have the millennials and young people driving anymore," he said. "You've got an aging demographic that's driving less. And the average car is 11.4 years old. When you turn that over, you get a lot better mileage. "