Wholesale prices fall even faster, suggesting that  prices at the pump should continue to decline.
"Nearly every part of the country should see a decline by the end of next week," said Tom Kloza, head of energy analysis for the Oil Price Information Service.
"[Gas prices] should continue sinking as we move through the summer," Kloza said. "It is very likely that we will pay less than $ 2.50 in the next few months."
The national average price is likely to drop further over the course of the year – perhaps to $ 2.25 a gallon, Kloza said. As soon as the summer driving season ends, the demand for gasoline decreases, which lowers prices. A shift away from the more expensive gasoline blend needed to control smog during the summer months.
A national average of $ 2.25 per gallon would probably mean that nearly half of the country's gas stations sell regular gallon for less than $ 2 a gallon, Kloza said.