In the middle of the last century, national economic growth
translated into a more broadly shared prosperity. As
productivity increased and the economy expanded, income
gains were relatively even across the distribution.
In contrast, a disproportionate share of income gains in
recent decades has accrued to the very top of the
distribution, in spite of continued productivity gains.
As a result, the gap between the incomes of those at the
high end of the distribution and those at the low end and
middle has widened significantly.