Recent research from the St. Louis Fed's Center for Household Financial Stability attempts to overcome these problems by adopting a demographic definition of the middle class. And it makes a difference. As the authors, William Emmons and Bryan Noeth noted, changing the definition reveals that "the middle class may be under more financial pressure than has been otherwise reported."
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Comparing income in 2013 with income in 1989 for each of these three groups, the researchers found little change in the median income of Thrivers and Stragglers. For Thrivers, median income rose 2 percent over this time period, while for Stragglers it rose 8 percent. However, for the Middle Class, median income fell by 16 percent between 1989 and 2013.
