Gas prices continue to head south this summer. Prices statewide have dropped to $2.37, down another six cents in just a week. The national average price is $2.26 per gallon, and Nashville residents are paying $2.29. Last year around this time, the average price per gallon in Illinois was $2.95. Analysts say that these summer gas prices are the lowest since 2005, though it is possible that a price correction in the Midwest is possible. South Carolina has the cheapest average gas prices in the country at just $1.95 per gallon. California’s prices are the highest in the nation at $2.91. According to one survey, record numbers of motorists are taking advantage of the low prices by hitting the road this summer.