(CNN) - Prices at the pump fell 23 cents per gallon over the past two weeks, according to a survey released Sunday.

The average price of a gallon of self-serve regular was $2.43, the Lundberg survey found.

That was about 20 cents lower than it had been a few days before Hurricane Katrina hit.

It was also 41 cents higher than the average a year ago.

The survey of gas stations in all 50 states was carried out Friday.

Publisher Trilby Lundberg said prices have been tumbling as refining capacity has been restored following hurricanes in the Gulf region. Also, imports have increased, while demand has dropped.

Americans traditionally drive less as fall sets in. And the historically high prices have reduced demand, Lundberg said.

A survey two weeks ago found the price had fallen 25 cents over the previous two weeks.

Lundberg said Sunday she expects "more price cuts, but at a much smaller rate than we've seen for the past month," as more refining facilities are repaired and as the lower prices encourage some people to drive more.

The lowest average price the survey found was in Tulsa, Okla., where drivers paid an average of $2.06 for a gallon of self-serve regular. The highest average price was in Miami, at $2.74. (See correction.)

Here are some other average prices for a gallon of self-serve regular:

San Francisco - $2.64

Chicago - $2.52

Denver - $2.40

Atlanta - $2.35

Philadelphia- $2.38

Omaha, Neb. - $2.17

Detroit - $2.23

Honolulu - $2.72

Anchorage - $2.53

Correction: An earlier version of this story said Tulsa, Okla. had the highest average gas price. The price in Tulsa is actually the lowest of all the cities that were surveyed. CNN/Money regrets the error. (Return to story.)