DEARBORN, Mich. (AP) – AAA Michigan says gas prices statewide have decreased by about 13 cents in the past week. The Dearborn-based auto club says the average price for self-serve regular unleaded gasoline was about $2.47 per gallon on Sunday. That’s about 43 cents less than it was at the same point last year. This is the second week in a row that the statewide price of gas has decreased by double-digits. The lowest average price was about $2.30 per gallon in the Traverse City area, while the highest average was about $2.51 per gallon in the Ann Arbor area.