|calculated using corrected formula and sanitized Social Security Medicare flat tax data|
The blue line represents a perfect flat distribution of income. The bottom 10% according to this ideal gets 10% of the income, and the bottom 30% gets 30% of the income, and the bottom 70% of earners gets 70% of the income. The green line represents how much income those fractions of the population actually get. The more the green line sags, the greater the Gini Coefficient.
0.542 (much better than the old .0608 calculated with a mistake from erroneous data but still) puts the US in league with Africa and Central America. A low Gini coefficient is a mark of civilization. A high one is trouble. Countries with bad income disparity don't have vibrant economies. The same supply-sider arguments against progressive taxation dragging on the economy also apply to an oligarchy distorting markets. Now that the economy is not growing, there's no "increasing the whole pie" argument to stave off "why is my slice so small?"