The federal poverty threshold for a family of four is just under $24,000; however, Americans believe such a family unit living in their community needs more than double that — $58,000, on average — just to "get by.
Hmmm. By coincidence, that's almost exactly the median income of an American family. It makes you suspect that most people think their own income, by definition, is just barely enough to get by. Turns out that's almost the case:
Adults in households earning less than $30,000 think it takes an average of $43,600 to get by. However, the estimate rises to $55,100 among those earning between $30,000 and $74,999, and to $69,400 among those making $75,000 or more.
Poor people think they need a bit more than their own income; middle class folks think their own income is just barely sufficient; and upper middle folks are willing to concede that they could get by on slightly less than they make. Still, to a pretty close approximation, whatever income we make turns out to be the income we consider barely sufficient.