evidence: A quiet city on the edge of the Ozarks is the only town in the entire country where the average price of gas is less than $2 a gallon. [...] The national average stands a $2.45 a gallon, the lowest since 2009. As of Friday, half of all states had at least one station selling gas for less than $2, twice as many as on Monday. And Alaska and Hawaii are the only two states with an average gas price above $3 a gallon.