You may have a little extra cash in your pocket when you pull away from the gas pump in coming months.

Gas prices are set to dive this fall, according to GasBuddy.com, which monitors and analyzes the market across the country.

“Before Christmas, as many as 20 states could have average gas prices below $2 per gallon,” the group projected on Friday.

Gas prices have been in a slide since spring 2014, though with a bump up earlier this year. They are still well below levels of a few years ago — and about to head lower, the group said.

The national average for regular gasoline in December will fall to $1.98 – down from $2.67 a gallon today, GasBuddy projected.

Georgia’s average price is currently $2.51 a gallon, while metro Atlanta’s is $2.61. The county with the lowest average is Lamar at $2.45. Fulton County’s average is highest, $2.72 a gallon.

A year ago, the average price in metro Atlanta was $3.46 a gallon, according to GasBuddy. But it fell through the summer and fall, hitting $2 a gallon in late January of this year.

Atlanta’s average price hit a five-year high of $4 a gallon in 2011, although it was slightly higher in the aftermath of hurricanes Katrina and Rita in 2005.

Generally, gasoline moves in parallel with global oil prices and the world has seen those prices plunge in the past two years. A combination of weak demand and fresh supplies – especially from the United States – has kept pushing those prices down.

Despite predictions that the falling prices would cause many of the new American rigs to go dry as companies went broke, production has not yet plunged as expected by some.

The federal government projections are a little less rosy than GasBuddy's. Average prices nationwide will bottom at about $2.27 a gallon in December but will be $2.55 for all of 2016, according to the Energy Information Administration.