Diesel and gasoline prices dropped again in the first week of December, setting new lows for the year, according to the latest numbers from the Energy Department.

The average price of a gallon of on-highway diesel fuel decreased 4.2 cents for the week, dropping to $2.379. The price is down considerably compared to the same week a year ago, coming in $1.156 cheaper year-over-year.

The largest decrease in prices was seen in the Midwest, dropping 6.3 cents per gallon week-to-week. The smallest change came to New England, where prices fell 1.2 cents per gallon.

Average gasoline prices were down but nearly flat for the week, decreasing 0.6 cents and settling at $2.053 per gallon. The price is 62.6 cents cheaper than it was in the same week in 2014.

Gasoline were down in most locations, with the largest decrease occurring in the Rocky Mountain region at 3.8 cents per gallon. There was a slight increase in the Midwest with prices rising 1.3 cents per gallon.

The price of crude oil hovered around 7-year lows on Tuesday, dropping on news that OPEC would be maintaining high production output despite a global drop in demand, according to a Market Watch report. While oil production has slowed somewhat this year, it still remains near 9 million barrels a day.