Yes, the “middle-class is disappearing” as we hear all the time, but it’s because middle-income households in the US are gradually moving up to higher income groups, and not down into lower-income groups. In 1967, only 9% of US households (only 1 in 11) earned $100,000 or more (in 2017 dollars). In 2017, more than 1 in 4 US households (29.2%) were in that high-income category, a new record high. In other words, over the last half-century, the share of US households earning incomes of $100,000 or more (in 2017 dollars) has more than tripled! At the same time, the share of middle-income households earning $35,000 to $100,000 (in 2017 dollars) has decreased over time, from more than half of US households in 1967 (53.8%) to less than half (only 41.3%) in 2017. Likewise, the share of low-income households earning $35,000 or less (in 2017 dollars) has decreased from more than one-third of households in 1967 (37.2%) to below one-third of US households last year (29.5%), a near-record low.

Mark J. Perry, “America’s middle class is disappearing … but it’s because they’re moving up.”, July 30, 2019, aei.org. Emphasis in the original.