The average cost of diesel in the United State has fallen for the fourth straight week. A new U.S. Energy Department report shows it dropped 4.1 cents over the past week to $4.006 per gallon.

This follows diesel hitting its highest average price of $4.159 per gallon since August 2008 during the final week of February. Compared to a year ago, the average cost is 14.1 cents per gallon lower.

Prices fell in all regions of the country with the biggest drop recorded along the West Coast, losing 6.1 cents for an average of $4.10.1, also positioning the area to have the third highest diesel prices in the country.

Average costs ranged from a high of $4.171 per gallon in New England, one of three East Coast sub-regions, to a low of $3.935 in the Gulf Coast and Rocky Mountain regions. The New England region recorded a decline of 3.3 cents, the Gulf Coast 5.4 cents and the Rocky Mountain region dropping 3.6 cents.

Other regional prices and weekly changes:

• East Coast (made up of the New England, Central Atlantic and Lower Atlantic regions), $4.05, down 3.2 cents.

• Central Atlantic, $4.109, down 3.1 cents.

• Lower Atlantic, $3.983, down 3.3 cents.

• Midwest, $3.979, down 3.6 cents.

• West Coast, $4.101, down 6.1 cents.

• California, $4.147, down 6.5 cents.

Like diesel, gasoline also continued its trend of moving lower for the fourth straight, falling 1.6 cents over the past week for a national average of $3.68 per gallon. Compared to the same time a year ago it is 23.8 cents per gallon less.

Prices declined in all regions but the Midwest, where it gained 1.2 cents for $3.657 per gallon. Gasoline ranges from a low of $3.469 in the Rocky Mountain region, where it is unchanged over the past week, to a high of $3.962 along the West Coast, down 4.5 cents.

Oil hit its highest level in more than a month by the close of trading Monday in New York. It gained $1.10 for the day, setting at $94.81 per barrel. Crude moved somewhat higher over the past week following news from the U.S. Energy Department last week that stockpiles have declined. It continued the gain into Monday following news that Cyprus had reached a deal with international lenders avoiding a government bankruptcy. Over the past week oil is up just over a dollar per barrel.