While the Framers of the American Constitution were “pretty smart,” they had no experience with the type of representational inequality of today’s Senate. The Gini index of representational inequality in the Senate was 0.342 in 1790 and was 0.506 in 2015, the latest date from the data. This is an enormous change—in the income inequality literature, a change of 0.03 is considered “salient.”1
Another way to think about this, rather than with the difficult to interpret Gini, is the “social tables” approach preferred by Piketty.