I should say, however, that while 100,000 [net entrants to the labor force] per month appears to be the right benchmark for the next year or two, there is a lot of uncertainty about this benchmark, particularly in the longer run. Some of this uncertainty revolves around the participation of the baby boomers. People are living longer, healthier lives, which may allow baby boomers to work until they are older. Moreover, wages for all workers may change in response to these trends, convincing some to work more, and others to work less, than they would otherwise.
....Putting together our best estimates of the trends of labor force growth and productivity growth, we at the Chicago Fed think potential GDP growth is lower than it was five years ago, and currently is somewhat below 3 percent.