As the population grows each year, how have they moved into the economy? Are things different this time?
Starting with BLS annual data for Civilian noninstitutional population 16 years and over, Civlian labor force 16 years and over and Not in labor force 16 years and over I took the year over changes for each series and constructed plots:
Looking at the changes in the over 16 population and labor force, we see only three years in which the year over year change in the labor force was negative - 1951, 2009 and 2010 - and the 1951 event is characterized by the only year over year decline in the civilian population. In fact, the year over year change for all three series was negative in 1951. This is not the case in 2009 and 20010, where there is ~1% population growth, year over year declines in the labor force, and year over year increases in not in the labor force (seen in following graph).
Here we see the population changes and the not in labor force changes, and there are three years that stand out for the increase in not in the labor force being greater than the increase in population (excepting 1951 op cit) - 1976, 2009 and 2010 - with by far the largest outlier being the 1976 data point.
In summary, it is clearly different this time, as only 2009 and 2010 year over year changes show consecutive declines in the size of the labor force and consecutive year over year increases in the not in labor force greater than the increases in population.