The average price of a gallon of unleaded increased 7.8 cents to $2.24 for the week ending May 2, according to federal records.

Gasoline is now 42.4 cents lower than it was a year ago, and the price increased most in the Lower Atlantic region, increasing 11.2 cents to $2.163. The slightest increases came on the West Coast (3.9 cents to $2.635) and West Coast without California (4.8 cents to $2.334), according to the U.S. Energy Information Administration.

Among states, California ($2.802) and Hawaii ($2.58) remain above $2.50 per gallon. Most of the remainder sit above the $2 level with the exception of Kansas ($1.995), Missouri ($1.986), Texas ($1.983), and Oklahoma ($1.961), according to the AAA's Daily Fuel Gauge Report.

Meanwhile, the average price of a gallon of diesel increased 6.8 cents to $2.266 per gallon. Diesel now costs 58.8 cents less than a year ago.