It's not just that the average IQ in Arizona is 48th in the nation (at 95.5) or that on average, only 84 percent of Arizonians graduate high school. What gives Arizona this big dumb prize is the fact that as of 2012, the state's largest employer is (drum roll please.) Walmart. Yep, in Arizona, more people work at Walmart than anywhere else. Now quick, think of the ten smartest people you know. How many of them work at Walmart? That's what I thought.