The series comes from the 'Current Population Survey (Household Survey)'
The source code is: LNU03023653
Source: US. Bureau of Labor Statistics
Release: Employment Situation
US. Bureau of Labor Statistics, Unemployment Level - Job Losers on Layoff [LNU03023653], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/LNU03023653/, June 3, 2015.