Diesel prices were down for the second week in a row, falling 2.2 cents this week to a national average of $2.957 a gallon

, according to weekly figures released by the U.S. Energy Information Administration.

Prior to the declines, diesel climbed a total of 9.2 cents in three weeks. Two weeks ago, trucking's main fuel jumped to its highest average since May. This week's average is 28.9 cents higher than the same week last year.

Diesel hovered above $3 a gallon in a few regions around the country, including the West Coast and Central Atlantic, which posted the highest averages at $3.114 and $3.038 a gallon, respectively. The Lower Atlantic and Gulf Coast regions had the lowest averages, at $2.910 and $2.916 a gallon, respectively.

After closing at a six-week low Friday, crude oil continued to slip Monday, along with U.S. equities and the strengthening of the dollar, according to reports by MarketWatch. Oil settled 1 percent lower, to $73.10 a barrel on the New York Mercantile Exchange.

Lately, oil activity has reflected stock market performance, which investors look to as an indicator of economic conditions, MarketWatch reports.