“Traditionally one of the most stable measures” in the General Social Survey, the number of Americans who consider themselves middle-class has dropped in recent years across multiple surveys:

Since 2008, the number of people who call themselves middle class has fallen by nearly a fifth, according to a survey in January by the Pew Research Center, from 53 percent to 44 percent. Forty percent now identify as either lower-middle or lower class compared with just 25 percent in February 2008.

According to Gallup, the percentage of Americans who say they’re middle or upper-middle class fell 8 points between 2008 and 2012, to 55 percent.

And the most recent General Social Survey, conducted by NORC at the University of Chicago, found that the vast proportion of Americans who call themselves middle or working class, though still high at 88 percent, is the lowest in the survey’s 40-year history. It’s fallen 4 percentage points since the recession began in 2007…

Why do so many no longer regard themselves as middle class? A key reason is that the recession eliminated 8.7 million jobs. A disproportionate number were middle-income positions. Those losses left what economists describe as a “hollowed out” workforce, with more higher- and lower-paying and fewer middle-income jobs.

At this point, perhaps recession isn’t the best word to use. Rather, perhaps we should speak of a larger restructuring of the American economy that was in the works for quite a while but accelerated with the housing bubble burst. For example, certain job trends – like the loss of manufacturing jobs, the rise of service jobs, the increasing globalization of labor – have been present since the 1970s. But, a whole bunch of things converged in recent years including increased consumerism, bad loans and debt, and changing job trends.

Another part of this is harder to ascertain: just who are Americans comparing themselves to when they think about the middle-class? The top 1% or the top .01%? The celebrities and characters they see on TV? The median household income in the United States is around $50,000 so earning around there would make one middle-class. However, that yearly income doesn’t necessarily buy the sorts of amenities Americans might think they need to be securely in the middle-class. Put another way, the perceived needed standard of living may have increased even as average incomes have not changed much.