The percentage of Americans whose incomes place them in the "upper middle class" more than doubled between 1979 and 2014, according to Stephen J. Rose of the Urban Institute. In the study, Rose defines the upper middle class as people in households with incomes ranging from $100,000 to $349,999 after adjusting for household size—or what he calls "family-of-three" equivalents. The upper middle class includes single-person households with an income of $57,735 or more, for example, and two-person households with an income of $81,650 or more.
Since 1979, the upper middle class has grown from just 12.9 to fully 29.4 percent of Americans. At the same time, the upper class expanded from 0.1 to 1.8 percent of the population. All other income classes shrank during those years...
Income Class as a Share of U.S. Population in 2014 (and 1979)
Upper class: 1.8% (0.1%)
Upper middle class: 29.4% (12.9%)
Middle middle class: 32.0% (38.8%)
Lower middle class: 17.1% (23.9%)
Lower class: 19.8% (24.3%)
"The striking finding is the change in the center of gravity in the economy," says Rose. "In 1979, 70 percent of the incomes were controlled by the three bottom groups. In contrast, in 2014, 63 percent of incomes were held by the upper middle class and the rich and just 37 percent by the bottom three groups." In the future, Rose plans to examine the changing demographics of the upper middle class—such as educational attainment and marital status—to determine the cause of its enormous growth. One causal factor that should be examined is the aging of baby boomers from young adulthood in 1979 to their peak-earning years in the 2000s. Will the size of the upper middle class shrink as boomers retire?
Source: Urban Institute, The Growing Size and Incomes of the Upper Middle Class