The average price of regular-grade gasoline has dropped 22 cents a gallon over the past three weeks, to $2.51, according to an Associated Press report.  Analysts say that falling crude oil costs are the main reason for the decrease at the pump. The average gas price has dropped 40 cents in the past three months.

The highest average price in the nation is $3.58 a gallon in the San Francisco Bay Area. The lowest average is $1.91 in Tulsa, Oklahoma.

According to the cheapest gas in Martinsville is at the Liberty Street Market and CITGO on Liberty Street both at $2.09 per gallon. Kroger on Commonwealth Boulevard is reported next at $2.19.