Gas prices fell for the 21st straight day Thursday as the AAA travel services organization estimated that at least a third of gas stations across the country were selling regular unleaded for less than $3. The national average for a gallon of regular unleaded gas was $3.16, according to the AAA Daily Fuel Gauge Report, 9 cents less than a week ago and 22 cents less than a month ago.
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Regular unleaded averaged less than $3 in 13 states, with Missouri posting the lowest average at $2.84. Most of the under-$3 states were in the South, where low state gas taxes help keep prices down, but the list included Delaware, where the average price was $2.99; New Jersey, $2.98; and Minnesota, $2.95. Motorists in St. Louis were paying even less than the Missouri statewide average, at $2.79 a gallon, according to AAA, among the lowest for major U.S. cities.