The series comes from the 'Current Employment Statistics (Establishment Survey)'
The source code is: CEU4200000003
Source: US. Bureau of Labor Statistics
Release: Employment Situation
US. Bureau of Labor Statistics, Average Hourly Earnings of All Employees: Retail Trade [CEU4200000003], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/CEU4200000003/, August 30, 2015.