As the economy continues to recover from the Great Recession, the unemployment rate in New Jersey and across the nation continues to drop, but the news may not be as good as it seems.

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"The perception that the unemployment rate is dropping substantially, if not exclusively, due to labor force withdrawal is correct," said Pat O'Keefe, director of economic research at CohnResnick.

O'Keefe said the labor force participation rate was declining slowly before the recession, in large part because people were becoming affluent and they were moving toward their retirement. However, things have changed over the past five years.

"There has been a sharp acceleration in the declines of the labor force participation rate, and most of that decline has been concentrated in the prime work-age years," O'Keefe said.

O'Keefe added, "It's not occurring where we would expect to see it among the retirees; in fact, labor force participation for those over the age of 55 has increased. The decline has been concentrated among those who are 20 years of age to 54 years of age."

So what does this mean?

"A lot of them probably have extended their stay in school and in doing so they are more likely to be living at home with their parents or, as we see quite often, groups of individuals sharing the rent in order to make ends meet while they continue their education," he said.

O'Keefe said these under-employed millennials may on occasion be able to pick up some "grey" economy kind of employment -- everything from working on somebody's house to taking care of children -- but not any full-time work.