After climbing 19 cents over the last five weeks, diesel prices fell slightly this week to a national average of $2.939 a gallon.

Diesel prices were down 0.7 cents nationally, according to the Department of Energy.

Prior to the gains, which started around mid-February, diesel had dropped 12.3 cents over a five-week period. This week's average is 71.8 cents greater than the same week last year.

Despite the slight decrease, diesel prices still exceeded $3 a gallon in many areas of the country, including the Central Atlantic and New England regions, where prices averaged $3.075 and $3.029 per gallon, respectively. These areas saw the highest prices, whereas, the Gulf Coast and Midwest regions had the lowest averages, at $2.899 and $2.910 a gallon, respectively.

Meanwhile, oil prices were up Monday on strong economic signs and concerns over terrorist bombings in Moscow, according to reports by the Associated Press. Two female suicide bombers set off explosions in the subway in Moscow Monday, killing at least 38 people and injuring more than 60, the AP reports. The threat of future attacks may restrict oil supply from the country, and this has affected prices, according to the news service.

Crude oil was up $2.17 Monday and closed at $82.39 a barrel on the New York Mercantile Exchange.