Prices at regions tracked by DOE were mixed, with the East Coast, Gulf Coast and West Coast down less than a cent a gallon.
After three weeks of increases, the average weekly retail on-highway diesel price dropped this week.
For the third consecutive week, the average weekly retail on-highway diesel price increased, rising 0.7-cent to $3.073 a gallon.
DOE raised its diesel-price forecast for the rest of this year by 3 cents to $2.96 a gallon, and for 2011 by 4 cents to $3.14.
The national average price is 46.6 cents higher than the same week last year and the highest since $3.094 the week of May 17.
The on-highway diesel price increased this week, jumping 4.9 cents to $3 a gallon.
The national average price is 35 cents higher than the same week last year.
The price, which has climbed 2.9 cents since Sept. 6, is 33.8 cents higher than the same week last year.
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