HOUSTON, March 26 (Xinhua) -- U.S. crude oil imports increased but exports decreased during the week ending March 21, the U.S. Energy Information Administration (EIA) said Wednesday.

U.S. crude oil imports averaged 6.195 million barrels per day (b/d) last week, up by 810,000 b/d from the previous week, while crude oil exports averaged 4.609 million b/d, down by 35,000 b/d, according to the EIA's Weekly Petroleum Status Report.

Over the past four weeks, U.S. crude oil imports averaged about 5.716 million b/d, down by 11.0 percent from the same four-week period last year, crude oil exports averaged about 4.170 million b/d, down by 1.0 percent, according to the report.

The United States has been one of the world's important oil producers in the past years with the help of its shale oil production growth.