Diesel prices in the U.S. were down for the second week in a row, taking back some of the gains from the start of he year, according to the latest numbers from the Energy Department.

The average price of on-highway diesel fuel fell by 1.6 cents last week, settling at $2.569 per gallon at the pump. That price is still much higher than it was at this point last year, gaining nearly 50 cents compared to 2016.

The drop in average fuel prices was driven mostly by a 2.9-cent decrease in the Midwest, topping all other major regions in the U.S. New England was nearly flat over the same period, losing 0.1 cents for the week.

The average price of regular gasoline was down even more last week, dropping 3.2 cents to $2.326 per gallon. The price of gasoline is currently 47 cents more expensive than it was in the same week a year ago.

By region, the largest decrease in prices occurred in the Midwest, where prices fell by 6.4 cents per gallon. The smallest drop was on the West Coast, where gas prices fell by an average 0.7 cents.

Fuel prices seem to be mirroring the crude oil market, as the price of a barrel of crude oil was down in trading to start the week.  Oil prices were trending upward to start the year in anticipation of a deal between OPEC countries to freeze or cut oil production. However, the deal has also reignited U.S. crude oil production, which has subdued any gains, according to a MarketWatch report.

OPEC originally agreed to cut oil production to meet lower global demand and drive up crude oil prices. However, the resulting increase in prices made the U.S. oil industry, particularly the shale oil portion, profitable enough to ramp up production again. This has offset the anticipated price gains, at least in the short term.