The national average U.S. retail price of diesel fuel fell from the previous average of $1.746 to $1.734, the Department of Energy reported June 7.

Once again, the highest prices in the nation were in California, where the average cost is $2.121.

Among the higher prices were New England, at $1.816; $1.921 in the Rocky Mountain region; the Central Atlantic region, at $1.792; and on the West Coast, where the average price is $2.063.

Other prices include the Lower Atlantic region, where the average price is $1.649; the Midwest, at $1.675; the Gulf Coast, at $1.655; and the East Coast, at $1.700.