Series Is Presented Here As Two Variables--(1)--Original Data, 1920-1948 (2)--Seasonally Adjusted Data, 1932-1962. Source: NBER Computed Data By Multiplying Series 08010 (Production Worker Employment) By Series 08029 (Average Hours Worked Per Week) Converted To A 1957-1959=100 Base.
This NBER data series m08265b appears on the NBER website in Chapter 8 at http://www.nber.org/databases/macrohistory/contents/chapter08.html.
NBER Indicator: m08265b
Release: NBER Macrohistory Database
National Bureau of Economic Research, Index of Production Worker Manhours In Manufacturing, Total for United States [M0865BUSM350SNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M0865BUSM350SNBR, February 9, 2016.