Answer :
Several factors have contributed to the shrinking size of the American middle class after the early 1970s. One of them includes "the emergence of the low-wage service sector."
Other factors that contributed to the shrinking size of the American middle class during this period include:
Greater demand for higher-skill jobs;
The huge income gap between the high paid executives and employees in the middle ranks;
Fewer opportunities for those with little education.
Global competition and advancement in technology;
Surging education fees, health care, and housing cost;
Hence, in this case, it is concluded that the middle class in the United States is smaller today compared to the time before 1970.
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