Their share of the nation's income being much smaller than it was in 1970
is True.
In the 1970s , the lower class American's income was around 62 percent and
this has dropped to around 41 percent in recent times. The higher class
American's income however increased during the same period of time.
This is as a result of the increase in economic inequality of the country in
which the disparity between the income of the lower and higher class is very
wide.
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