And, most sobering, Mr. Mamet writes in "The Secret Knowledge, " there are no perfect solutions to inequality, only trade-offs.

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In the Gini measurement, zero means perfect equality and 1 means total inequality.

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The Gini index ranges from 0, which represents perfect equality, to 1, for absolute inequality.

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The Gini index, which measures inequality, has declined from 64 in 1989 to 56 in 2009 where an index of 0 means perfect equality (the US Gini index was 45 in in 2009).

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