In the December edition of its monthly Short-Term Energy Outlook released this week, the DOE's Energy Information Administration forecasted annual average diesel fuel retail prices at $2.46 and $2.96 per gallon for 2009 and 2010, respectively

. Meanwhile, the agency reduced its estimate for West Texas Intermediate crude oil to $76 a barrel for the winter, a $1 off from its November projection.

The EIA boosted its energy price forecast for diesel for 2010 by 2 cents, up from last month's $2.94 a gallon projection. However, diesel prices have been slowly falling over the last five weeks, settling at $2.772 Monday.

Over the last five weeks, trucking's main fuel has dropped 3.6 cents. Prior to the declines, diesel prices had gained 22.6 cents.

Crude oil is expected to dip to $75 a barrel early next year then rise to $82 a barrel by December 2010, as U.S. and world economic conditions improve, the EIA says.

Meanwhile, gasoline prices should also go up as crude oil increases, with projections of $2.35 per gallon in 2009 and $2.83 in 2010. The EIA expects gasoline to reach near $3 per gallon during next year's driving season.