Source: US. Bureau of Labor Statistics
Release: Employment Situation
Construction employees in the construction sector include: Working supervisors, qualified craft workers, mechanics, apprentices, helpers, laborers, and so forth, engaged in new work, alterations, demolition, repair, maintenance, and the like, whether working at the site of construction or in shops or yards at jobs (such as precutting and preassembling) ordinarily performed by members of the construction trades.
The series comes from the 'Current Population Survey (Household Survey)'
The source code is: LNU03032231
US. Bureau of Labor Statistics, Unemployment Level: Construction Industry, Private Wage and Salary Workers [LNU03032231], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/LNU03032231, August 23, 2016.