The average price of regular gasoline in the United States was virtually unchanged over a two-week period, dipping only 42 cents to $2.85.

That's according to the national Lundberg Survey of fuel prices released Sunday.

Analyst Trilby Lundberg says the average price for a gallon of mid-grade was $2.97. Premium was at $3.09.

Tulsa, Okla., had the lowest average price among cities surveyed at $2.60 a gallon for regular. Honolulu was highest at $3.47.

Diesel was at $3.08, up 2.59 cents from two weeks ago.

In California, the average price for a gallon of regular down 1.14 cents to $3.05.

Stockton had the state's least expensive gas at $3.01 a gallon. San Francisco was the steepest at $3.09.