The series comes from the 'Current Population Survey (Household Survey)'
The source code is: LNU03023706
Source: US. Bureau of Labor Statistics
Release: Employment Situation
US. Bureau of Labor Statistics, Job Leavers as a Percent of Total Unemployed [LNU03023706], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/LNU03023706/, August 1, 2015.