The Unequal State of America: How we calculated inequality

Using Gini, inequality has risen in each of the past two decades. Between 1989 and 2011, the index rose 6 percent nationally, to its highest level since the Census started measuring it in the 1960s. It rose in 49 of the 50 states. And it was rising even before the Great Recession struck. Between 1989 and 2007 - the last year for which data were unaffected by the slump - inequality rose 4 percent.
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