For the second straight week, the price of diesel fuel has increased after staying relatively flat for nearly two months, according to the latest numbers from the Energy Department.

The average price of on-highway diesel fuel increased by 3.6 cents last week, raising the price per gallon to $2.481 at the pump. Diesel fuel is still 5 cents cheaper than it was in the same week a year ago.

Prices were up in all major regions of the U.S. with the largest price increase occurring in the Midwest, jumping 4.1 cents for the week. The smallest change was in New England, where prices increased by 2.4 cents on average.

The average price of regular gasoline was down for the week overall, falling 1.5 cents and settling at $2.257 per gallon at the pump. The price is just barely cheaper than it was compared to the same week of 2015, down 2 cents by comparison.

Prices were actually up in most regions, but a 6.6-cent drop in the Midwest offset the mostly higher prices elsewhere. The largest increase was in the Rocky Mountain region, where it was up 2.5 cents.

Crude oil prices continue to be volatile as prices were down again on news that oil production was up locally and globally, according to a MarketWatch report.

This comes despite a tentative agreement between OPEC member countries to freeze output to reduce the supply glut globally. Recent reports showed that there was increased drilling for oil in the U.S. while OPEC countries like Iran have steadily increased production every month since sanctions relief has brought it back into the global oil market.

U.S. crude oil production is projected to be 8.7 million barrels per day this year, down from 9.4 million barrels per day in 2015.