Diesel fuel prices continue their slide downward to the $2 mark, with a gallon of diesel averaging $2.087 nationwide according to weekly figures released Monday by the U.S. Energy Information Administration.

That's 4.3 cents less than a week ago and $1.571 less than a year ago. The highest prices were seen in the New England region at $2.472; the lowest in the Midwest at $2.03. Prices fell the most in California last week, where they dropped 7.5 cents per gallon to $2.144.

Meanwhile, crude oil prices fell $4.61 to settle at $40.15 a barrel on the New York Mercantile Exchange. Lower prices were prompted by the U.S. government's announcement of a sharp drop in the gross domestic product, according to published reports; a slower economy means less demand for oil and fuel.