This series is from the Current Population Survey (Household Survey) conducted by the Bureau of Labor Statistics. Labor force flows show the movements that underlie the net over-the-month changes in employment, unemployment, or not in the labor force.
Source: US. Bureau of Labor Statistics
US. Bureau of Labor Statistics, Labor Force Flows Employed to Not in Labor Force: 16 Years and Over [LNU07800000], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/LNU07800000/, August 3, 2015.