Columbia subject headings:
Hours of labor--United States--Statistics.
Labor supply--United States--Statistics.
Labor turnover--United States--Statistics.
Wages--United States--Statistics.
Harvard subject headings:
Hours of labor--United States--Statistics.
Labor supply--United States--Statistics.
Labor turnover--United States--Statistics.
Wages--United States--Statistics.
Princeton subject headings:
Hours of labor--United States--Statistics.
Labor supply--United States--Statistics.
Labor turnover--United States--Statistics.
Statistics.
Wages--United States--Statistics.