A Pew Research Center report found that, in 2015, 120.8 million adults qualified as middle class in the U.S. The figure is just below 50 percent of the total population, according to the Los Angeles Times.
In 1971, the group accounted for 61 percent of the population, and the rate has declined ever since. The parameters of what the Pew Research Center says constitutes middle class varies by income and household size.
Americans have traditionally identified themselves as middle class, even if they made less or more than median incomes. The decline in the middle class is expected to be a major subject in the 2016 presidential race, as the divide between the rich and poor continues to expand.