There's a flip side to that, though, Van Horn suggests: "As the economy gets stronger, as it continues to grow, eventually some of those discouraged workers will come back into the labor market, and we'll have a higher labor-participation rate."
But that hasn't happened—yet.
"We know that the reason unemployment is so high right now is pretty simple: employers haven't seen demand for their stuff pick up in a way that would require them to bring on more workers, put that factory back on line, get more people to work," said Heidi Shierholz, chief economist for the Economic Policy Institute, a labor-oriented Washington think-tank.
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"It's going to be this way for a while. We're in a long slog," Shierholz said, noting that the recession of 2007-2009 was the harshest downturn since the 1930s Great Depression.
"We really are in a recovery. Things are getting better," Shierholz added. "It is agonizingly slow. But we are going in the right direction."
It may be quite a while before the jobless rate falls back to 5 percent and below, long the informal standard pegged by economists as a typical employment level for non-recession times.