A new Pew Research Center report documents a “lost decade” for middle-income Americans, analyzing government data that shows a decline in economic well-being and exploring findings from a new survey that adults who describe themselves as middle class are somewhat more downbeat about their finances and their children’s future than they used to be.

According to data from the Census Bureau’s Current Population Survey, mean family incomes declined overall and for each income quintile from 2000 to 2010; this was the first decade since record-keeping began in the 1950s that all income quintiles declined.

In addition, based on data going back to 1970, households in the nation’s upper-income tier now take in a larger share of the nation’s aggregate households income than they used to, while the shares for the middle-income and lower-income tiers have declined.  One reason for this trend is that upper-income households have made larger income gains than other households over recent decades. In addition, the share of adults who are in the middle-income tier (defined as living in households with two-thirds to double the national median income) has shrunk in recent decades: 51% of adults resided in such households in 2010, compared with 61% in 1970.

Looking at wealth data from the Survey of Consumer Finances, the net worth of middle-income families also declined over the decade. Based on data from 2001 to 2010, median net worth–defined as assets minus debt–declined 28% for these families, erasing two decades worth of gains.

A new Pew Research survey, conducted from July 16-26, finds that 49% of American adults describe themselves as middle class; 53% said the same in a 2008 Pew Research survey. Among these self-described middle-class adults, 85% say it is more difficult than a decade ago for the middle class to maintain its standard of living.