Diesel fuel prices remained flat during the week ending Feb. 6, dropping by just four-tenths of a cent, according to the Department of Energy’s weekly update.

The average price of a gallon of on-highway diesel is now $2.558 nationwide following the fourth consecutive week of falling prices.

California and the West Coast less California were the only two regions in the U.S. during the week to see price increases. The largest drop in prices during the week came in the Midwest region, where prices fell eight-tenths of a cent.

The nation’s most expensive diesel can be found at California at $2.944 per gallon, followed by the Central Atlantic region at $2.763 per gallon.

The cheapest fuel is in the Gulf Coast region at $2.403 per gallon, followed by the Midwest region at $2.492 per gallon.

Prices in other regions, according to the DOE, are:

  • New England – $2.661
  • Lower Atlantic – $2.508
  • Rocky Mountain – $2.515
  • West Coast less California – $2.748

ProMiles’ numbers during the same week showed a decrease in diesel prices of eight-tenths of a cent to $2.505 per gallon nationwide.

According to ProMiles’ Fuel Surcharge Index, the most expensive diesel can be found in California at $2.89 per gallon, and the cheapest can be found in the Gulf Coast region at $2.412 per gallon.