Average retail pump prices in the U.S. for both diesel and gasoline increased slightly this week, according to data tracked by the Energy Information Administration (EIA), though prices for both remain at historically low levels.

The average retail price for diesel in the U.S. inched up 3/10ths of a penny this week to $1.983 per gallon, EIA reported. Though tiny, it's the first price increase since the first week of November. Even so, diesel is 91.7 cents lower per gallon compared to the same week in 2015.

Price increases occurred in two of the four regions of the country where diesel remains below the $2 per gallon mark:

  • The Midwest, up 1.3 cents to $1.921 per gallon
  • The Gulf Coast, up 1.5 cents to $1.873
  • The Rocky Mountains, down 5/10ths of a penny to $1.861
  • The Lower Atlantic, down 3/10ths of a penny to $1.944

Retail diesel prices on the West Coast, with California excluded, jumped up slightly by 7/10ths of a penny to $2.05 per gallon this week, EIA said. However, diesel in California declined 2.8 cents to $2.288 per gallon, so when included, the West Coast’s average dipped 1.3 cents to $2.181.

Average retail prices for gasoline increased 6/10ths of a penny this week to $1.73 per gallon, which is 60.2 cents cheaper per gallon compared to the same week in 2015, EIA noted.

A big 8.7 cent spike in the average retail price of gasoline in the Midwest region to $1.609 per gallon is responsible for that uptick in national retail average prices, counterbalanced by a 7.6 cent decline in West Coast prices to $2.141 per gallon (which becomes a 6.3 cent decline to $1.875 with California’s prices removed from the mix).

Still, the EIA’s recent Short-Term Energy Outlook (STEO) predicts that  retail prices for regular gasoline will average $1.98 per gallon in 2016, which would be the lowest annual average since 2004, jumping up to $2.21 per gallon in 2017.

Lower crude oil prices contributed to U.S. regular gasoline retail prices declining to an average of $1.95 per gallon in January, down from an average of $2.04 per gallon in December, the agency added.

EIA projects regular gasoline retail prices to fall to $1.82 per gallon in February and average $1.88 per gallon for the first quarter of 2016, before rising during the spring.

Retail prices for diesel, which averaged $2.71 per gallon in 2015, are projected to average $2.22 per gallon for 2016 before rising to $2.58 per gallon in 2017, the agency noted.

Continuing increases in global oil inventory is placing “significant” downward pressure on oil prices – a trend that started in mid-2014, EIA pointed out – and should continue to suppress both global oil prices and U.S. fuel prices.

After growing by an estimated 1.8 million barrels per day (b/d) in 2015, global oil inventories are predicted to grow by another 1.4 million b/d in the first quarter of 2016, helping keep Brent prices below $40 per barrel through August, the agency said.