Los Angeles ? Retail gas prices across the country climbed an average of 11 cents in the past two weeks, according to a new survey.

The weighted average price for all three grades increased to $2.38 a gallon by Friday, according to Trilby Lundberg, who publishes the semimonthly Lundberg Survey of 7,000 gas stations around the country.

Self-serve regular averaged $2.35 a gallon nationwide. Mid-grade cost $2.45 a gallon while the price for premium was $2.55.

Gas prices are 38 cents higher than they were a year ago, Lundberg said Sunday.

Among stations surveyed, the lowest average price in the country for regular unleaded was in Newark, N.J., at $2.15 a gallon. The priciest was $2.63 a gallon in Honolulu.