CAMARILLO, Calif. >> A national survey of gas prices reports that Americans are paying 12 cents on average less than they were three weeks ago.

Industry analyst Trilby Lundberg said Sunday that the average for regular grade gas is $3.26 per gallon, while midgrade averages $3.48 and premium $3.64. Retail diesel averages $3.74.

Lundberg said the price has decreased for 16 weeks, crediting lower crude oil prices.

She forecast further cuts of a dime or more, thanks to decreases in the price of crude oil and ethanol.

In the lower 48 states, San Francisco averaged the highest average price at $3.66 per gallon, while Tulsa, Oklahoma, had the lowest average at $2.93.