A survey says the national average price for gasoline rose 9 cents over the last two weeks to a record average of $3.20.

The average price of self-serve regular gasoline on Friday was $3.19 a gallon, mid-grade was $3.31 and premium was $3.42, according to the Lundberg Survey of 7,000 stations nationwide released Sunday.

But the worst is yet to come, analyst Trilby Lundburg told Bloomberg news.

''We will probably see 20 or 30 cents more at the pump very soon, possibly within a month,'' Lundberg said. ''This is all if crude oil prices don't slide substantially, and it doesn't seem likely that they will.''

The previous record high was $3.18, set last May, and that remains the highest average price when adjusted for inflation, according to Lundberg.

Of the cities surveyed, the cheapest price was in Cheyenne, Wyoming, where a gallon of regular cost $2.95, on average. The highest was in San Francisco at $3.58.

Compared to a year ago, national gas prices are up 64 cents.