The average retail price of a gallon of gasoline, including all grades and taxes, was about $1.15 on Friday, down more than 8 cents per gallon in the past three weeks, according to the Lundberg Survey of about 8,000 stations nationwide released Sunday.
It's the lowest price since March 1999, when the national average was about $1.08.
In some cities the average gas price dipped below a dollar a gallon, to the joy and amazement of drivers.
"It was $2 a gallon less than six months ago," said Jeffrey Spring, a spokesman for the Automobile Club of Southern California.
"Those good ol' days are back," said Cyndi Burrough, 49, as she filled her car for 99 cents a gallon at an Arco station in the San Fernando Valley. "Everybody, get your gas cans out."
Honolulu had the most expensive gas surveyed at $1.70 per gallon on average. In Atlanta, the average was just 90 cents.
In Yardville, N.J., drivers found unleaded gas for as low as 89 cents a gallon.
"Anything below a dollar is marvelous," said Leon Falardeau, who was filling up at a Gulf station.
The roller coaster ride for gas prices began in May, when the national average peaked at $1.76 per gallon.
"There had been pressure to prepare for summer driving. Demand was strong. An oversupply developed," analyst Trilby Lundberg said.
Prices bottomed out in August and began slowly rising until Sept. 11 when crude prices crashed amid the shakier world economy and uncertainty about U.S. retaliation. Americans did some panic buying but then became afraid to travel, irritating the usual seasonal drop in gas demand because of cold weather.
Crude oil prices have only recently begun rising. The Organization of Petroleum Exporting Countries wants to reduce production, but "weak economic conditions and swollen gasoline supplies are likely to keep pump prices low through New Year's and beyond," Lundberg said.
"All bets are off, however, if military action in the Middle East should spread to any oil-producing nations," she added.
Fear of flying and the low gas prices may yet raise winter demand.
A record 87 percent of Americans traveled by car this past Thanksgiving, and the Auto Club expects that will continue into the holiday season, Spring said.
By Christiana Almeida © MMI The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed