Series Is Presented Here As Two Variables--(1)--Original Data, 1895-1920 (2)--Original Data, 1919-1954. Source: Ralph L. Nelson, The Merger Movement In American Industry (NBER), An Unpublished Manuscript
This NBER data series q10093a appears on the NBER website in Chapter 10 at http://www.nber.org/databases/macrohistory/contents/chapter10.html.
NBER Indicator: q10093a
Release: NBER Macrohistory Database
National Bureau of Economic Research, Firm Disappearances By Merger, Manufacturing and Mining for United States [Q1093AUSQ475NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/Q1093AUSQ475NNBR/, October 9, 2015.