(c) 2014, Bloomberg News.

(c) 2014, Bloomberg News.

The average price for regular gasoline at U.S. pumps rose 11.67 cents in the past two weeks to $3.4111 a gallon, according to Lundberg Survey Inc.

The survey covers the period ended Friday and is based on information obtained at about 2,500 filling stations by the Camarillo, Calif.-based company.

The average retail price is 38.39 cents lower than a year ago, Lundberg said.

"It's due to crude oil prices and higher prices of ethanol which must be blended into gasoline," Trilby Lundberg, the president of Lundberg Survey, said in a telephone interview on Sunday.

The highest price for gasoline in the lower 48 U.S. states among the markets surveyed was in San Diego, at $3.82 a gallon, Lundberg said. The lowest price was in Billings, Mont., where customers paid an average $3.08 a gallon. Regular gasoline averaged $3.63 a gallon on Long Island, N.Y., and $3.81 in Los Angeles.

Gasoline futures on the New York Mercantile Exchange rose 8.44 cents, or 3.1 percent, to $2.8333 a gallon in the two weeks ended Friday. During the same period, West Texas Intermediate crude climbed $2.32, or 2.3 percent, to $102.20 a barrel on the Nymex.

Inventories of the motor fuel across the U.S. increased 309,000 barrels in the week ended Feb. 14 to 233.4 million, a three-year seasonal high, the Energy Information Administration reported on Thursday.

Refiners are shutting units for seasonal maintenance, reducing fuel production. Plants operated at 86.8 percent of capacity in the seven days through Feb. 14, down from 92.7 percent as of Dec. 20.