Change in U.S. median household income 1970-2014, by income tier

This statistic shows the change in the median household income per decade in the United States from 1970 to 2014, by income tier. Between 1990 and 2000, the median household income for the middle class increased by 12 percent.
This study defined middle class income households as those with an income between 67 and 200 percent of the U.S. median household income, after adjustment for household size. In 2014, the middle class income ranged from about 42,000 U.S. dollars to about 126,000 U.S. dollars per year for a three-person household.