CAMARILLO, Calif. (AP) — The average U.S. price of regular-grade gasoline went up by a penny over the past two weeks, to $3.25 per gallon.

That’s $1 more than a year ago.

Industry analyst Trilby Lundberg of the Lundberg Survey said Sunday the slight increase is due to a rise in the cost of crude oil.

Nationwide, the highest average price for regular-grade gas is in the San Francisco Bay Area, at $4.47 per gallon. The lowest average is in Houston, at $2.72 per gallon.

According to the survey, the average price of diesel was $3.35 a gallon, up a fraction of a cent.