Thanks to our friends at the Economic Policy Institute
for this illuminating chart. It's a little tough to read, so we'll repeat: Between 1919 and 1973, Average income in the U.S. grew by $29,955. The richest 10% got 30% of the growth. The bottom 90% shared 70%.
Here's what happened between 1973 and 2008: Average incomes in the U.S. grew by $9,268. All growth went to the richest 10%. Income for the bottom 90% declined.