A significant decline of 3 cents in the week ended September 30 to $3.919 for the on-highway diesel national average retail price. According to the Department of Energy’s Energy Information Administration, this is the biggest week-to-week decline since April 29.
Led by a 3.7-cent fall in the California subregion, the average price also dropped in all regions in the U.S. However, California still has the country’s highest diesel average, at $4.172 a gallon.
On the other hand, the Rocky Mountain region had the nation’s smallest drop, 1.6 cents, but has the largest year-over-year gap, at 27.8 cents lower than the same week in 2012.
The cheapest U.S. diesel average is in the Gulf Coast region, at $3.831.