The average U.S. price of regular-grade gasoline plunged 32 cents over the past two weeks to $4.54 per gallon.
Industry analyst Trilby Lundberg of the Lundberg Survey said Sunday that the continued decline comes as crude oil costs also fall.
"Further drops at the pump are likely as the wholesale gasoline price cuts continue making their way to street level," Lundberg said in a statement.
The average price at the pump is down 55 cents over the past six weeks, but it's $1.32 higher than it was one year ago.
Nationwide, the highest average price for regular-grade gas was in Los Angeles, at $5.65 per gallon. The lowest average was in Baton Rouge, Louisiana, at $3.90 per gallon.
According to the survey, the average price of diesel dropped 22 cents over two weeks to $5.55 a gallon.
Additional reporting by The Associated Press.