Source: For 1919-1930 Data, Bureau Of Labor Statistics Bulletin 623, "Wages, Hours, And Working Conditions In The Bread-Baking Industry, " P.16; For 1931-1934 Data, Bureau Of Labor Statistics Mimeographed Release, September, 1938, "Revised Index Numbers Of Factory Employment And Payrolls." P.31-32; For 1935-1939 Data, Bureau Of Labor Statistics Mimeographed Release, May, 1940; For 1940-1941 Data, Bureau Of Labor Statistics "Employment And Payrolls"; Thereafter, Monthly Labor Review
This NBER data series m08112 appears on the NBER website in Chapter 8 at http://www.nber.org/databases/macrohistory/contents/chapter08.html.
NBER Indicator: m08112
Release: NBER Macrohistory Database
National Bureau of Economic Research, Index of Factory Payrolls, Baking for United States [M08112USM331NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M08112USM331NNBR/, July 8, 2015.