The national average price of a gallon of unleaded gasoline has fallen to $2.178 per gallon where it's again nearing the six-year low it reached in early 2015, when it hovered about the $2 level.

The price fell 5.7 cents for the week ending Nov. 16, and the price is now 71.6 cents lower that its year-ago level.

Prices fell across the nine regions tracked by the U.S. Energy Information Administration with the sharpest decline registered in the Midwest, which saw a 13-cent decline to $2.085 on the week. The West Coast still has the most expensive gasoline at $2.636 per gallon, while the Gulf Coast is the cheapest at $1.926.

Four states now have gasoline above $2.50 per gallon, including Hawaii ($2.856), California ($2.80), Nevada ($2.67), and Washington ($2.515). At the other end of the spectrum, 11 states now have gasoline lower than $2. South Carolina's $1.912 price point is the nation's lowest.

Meanwhile, the average price of diesel fuel fell 2 cents to $2.482. Diesel is now $1.179 lower than a year ago.