The Energy Information Administration says ethanol output rose to the highest level in a month during the week ending on May 6.
Ethanol inventories increased for the first time in six weeks.
Ethanol production rose to an average of 991,000 barrels a day, up from 969,000 barrels during the prior week. It was also the highest level since April 8.
In the Midwest, which produces the most of any region in the country, production rose to 941,000 barrels a day, up from 915,000 the week before. It's also the highest level in the Midwest since April 8.
The Midwest was the only region that saw an increase. Gulf Coast and West Coast production levels remained the same at 24,000 and 9,000 barrels a day, respectively.
Rocky Mountain output dropped to 12,000 barrels a day, the lowest output since December. Ethanol inventories increased to 24.14 million barrels during the week, the highest since April 15.