“Two years ago, the average adjusted gross income (AGI) in Teton County, Wyoming was the highest in the nation at $142,048. But newly released data from the IRS show that in filing year 2010, the average AGI in Teton county had dropped a precipitous 43 percent, down to $80,827. Using the free Tax Returns application on the Transactional Records Access Clearinghouse (TRAC) website, you can examine the kinds of income flowing to taxpayers in every state and the more than 3,000 counties in the United States. Data cover tax filing years 1991 through 2010.”