The price of a gallon of regular unleaded fell 7 cents to $2.56 for the week ending Nov. 26, as pump prices head lower to reach some of the cheapest prices of 2018, according to AAA.

The national average was at its lowest in January at $2.49. It's most expensive price came in May when it reached $2.97.

"Trends are indicating that the month of December may bring some of the cheapest gas prices of the year," said Jeanette Casselano, AAA spokesperson. "Currently, 19 states already have gas price averages less expensive than a year ago so as U.S. gasoline demand remains low and supply plentiful, motorists can expect to save at the pump as long as the price of crude oil doesn't spike."

States with the largest weekly decreases include Ohio (down 14 cents), Kentucky (down 11 cents), Mississippi (down 11 cents), South Carolina (down 10 cents), Michigan (down 9 cents), Alabama (down 9 cents), Arkansas (down 9 cents), Georgia (down 9 cents), Illinois (down 9 cents), and Texas (down 9 cents).

States with the least expensive markets include Missouri ($2.18), Oklahoma ($2.21), South Carolina ($2.23), Texas ($2.24), Delaware ($2.24), Louisiana ($2.26), Mississippi ($2.27), Alabama ($2.27), Kentucky ($2.27), and Ohio ($2.28).

Meanwhile, the average price for a gallon of diesel fell 2.1 cents to $3.261, which is 33.5 cents lower than a year ago, according to the U.S. Energy Information Administration.