400k is rich in some areas but certainly not everywhere, that's way too sharp of a curve. Someone making 400k is already taxed at 35% federally plus whatever state and local so probably close to 50. The real issue is that after 500k the rates don't change where it should be increasing logarithmically. But really after a certain point there are way too many things that the rich do to reduce their tax burden that just aren't available to everyone else, that 100k or 400k person is in reality paying a much higher percentage than someone making a million a year much less billionaires.