AAA Michigan says gas prices statewide have risen by about 4 cents per gallon in the past week. The Dearborn-based auto club says early Monday that the average price for self-serve regular unleaded gasoline was about $2.16 per gallon. That’s about 22 cents less than it was at the same point last year. The lowest average price was about $2.09 per gallon in the Traverse City area, while the highest average was about $2.22 per gallon in the Saginaw, Bay City and Midland areas. AAA Michigan surveys daily fuel prices at 2,800 gas stations across the state.