The United States consumed 19.1 million barrels per day of petroleum products during 2010, making us the world’s largest petroleum consumer (22% of world total). The United States was also third in crude oil production at 5.5 million barrels per day. But crude oil alone does not constitute all U.S. petroleum supplies.
Altogether, net imports of crude oil and petroleum products (imports minus exports) accounted for 49% of our total petroleum consumption in 2010.
U.S. crude oil imports grew rapidly from mid-20th century until the late 1970s, but fell sharply from 1979 to 1985 because of a fall-off of demand for petroleum products that resulted from economic conditions, conservation, and improved efficiency. After 1985, the upward trend resumed, peaking at 10.1 million barrels per day in 2005, and stood at 9.2 million barrels per day in 2010. Petroleum product imports were 2.6 million barrels per day in 2010. Total exports were 2.3 million barrels per day in 2010, mainly in the form of distillate fuel oil, petroleum coke, and residual fuel oil.
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The United States Also Exports Oil Because the United States is the world’s largest oil importer, it may seem surprising that it also exports about 2 million barrels a day of oil, almost all of it in the form of refined petroleum products. Due to various logistical, regulatory, and quality considerations, it turns out that exporting some barrels and replacing them with additional imports is the most economic way to meet the market’s needs. For example, refiners in the U.S. Gulf Coast region frequently find that it makes economic sense to export some of their gasoline to Mexico rather than shipping the product to the U.S. East Coast because lower-cost gasoline imports are available from Europe.
http://www.eia.gov/energyexplained/index.cfm?page=oil_imports