By Devin Henry - 12/31/15 11:35 AM EST
The average price for a gallon of gas in the United States in 2015 was the second-lowest of the last 10 years, auto club AAA reported Thursday.
A gallon of gas averaged $2.40 in 2015, AAA said, or 94 cents cheaper than the average cost in 2014. Because of the low prices, Americans spent $115 billion less on gasoline this year than they did last year.
Gas prices in December have been especially low, the group said. The national average price of gas was $2.01 this month, or lower than it has been since March 2009.
Thursday’s average price of $2 per gallon is the lowest New Year's Eve average since 2008. And the average price for a gallon of gas in the U.S. dropped below $2 earlier this month for the first time since 2009.
Prices tend to tumble during the early winter months because people use less fuel. Refineries will soon shut down for seasonal maintenance, which could drive prices up a bit by the end of the season, AAA said.
But the group noted Thursday that gas prices could remain low next year as well. Analysts expect a glut of crude oil on the market throughout the year, which could keep gasoline prices low around the world and in the U.S. AAA warned, though, that if oil-producing nations limit their supplies, prices could go up.
Even so, the group estimated that the average price of gas in 2016 will be between $2.25 and $2.45 a gallon.