The average price of a gallon of on-highway diesel fuel was down again for the 10th consecutive week, according to the latest weekly numbers from the U.S. Energy Department.

The cost of diesel dropped by 5.5 cents, settling at a $2.668 cent per gallon average nationally. The price is $1.185 per gallon cheaper than the same time a year ago.

The largest decrease occurred in the Gulf Coast region where it dropped by 7.5 cents to $2.536 per gallon. The smallest drop was in the Central Atlantic division where the price dropped 3.3 cents to $2.885 per gallon.

Gasoline prices were also down by a similar margin to Diesel. Prices dropped 5.6 cents on average settling to a cost of $2.689 cents per gallon.

Regionally, the largest decrease occurred in the Midwest with a drop of 6.5 cents per gallon to $2.518 while the Rocky Mountain region saw the smallest drop at 2.8 cents to $2.828 per gallon.

The price of Brent Crude Oil dropped below $50 per barrel this week for the first time in six months, according to a report in the Wall Street Journal.  The drop was a result of increasing domestic and global oil production as the producers compete for customers around the world.