As oil prices dropped below $90 per barrel Monday, gas prices have slid lower as well.

According to AAA, regular unleaded gas prices are down 2 cents from Sunday to $3.502 per gallon. Prices have dropped 17 cents from last month.

Oklahoma has the nation's cheapest average gas at $3.121 per gallon. Only two states -- Alaska and Hawaii -- average more than $4 per gallon.

According to Gasbuddy.com, Oklahoma City has the lowest average gas price for a U.S. city at $2.976 per gallon -- the only major city under $3 per gallon.

The highest recorded average gas price was on July 17, 2008, AAA reported, when regular unleaded hit $4.114 per gallon.

Oil prices are down nearly 40 percent from record highs in July of more than $145 per barrel. The decline comes on worries that the spreading financial crisis will exacerbate a global economic slowdown and cut demand for crude oil.

Light, sweet crude oil for November delivery was down $4.69 to $89.19 a barrel in electronic trading on the New York Mercantile Exchange by late Monday afternoon in Singapore.