(Undated) – The national average for a gallon of regular unleaded slipped lower over the weekend. According to this morning’s numbers from GasBuddy.com, the current national average is $3.04 a gallon, down a nickel from Friday. Here in Illinois, the statewide average is $3.16 a gallon, three cents lower than Friday. Drivers in Indiana are paying an average of $2.88 a gallon, down five cents from Friday. Oklahoma has the lowest prices in the nation, down a nickel from Friday at $2.50 a gallon. California has the highest statewide average at $4.44, four cents lower than Friday’s average.