Source: The Volume Of Corporate Bond Financing Since 1900 (NBER), W. Braddock Hickman, 1953, Pp. 308-309, Appendix A, Table A-13
This NBER data series m10083 appears on the NBER website in Chapter 10 at http://www.nber.org/databases/macrohistory/contents/chapter10.html.
NBER Indicator: m10083
Release: NBER Macrohistory Database
National Bureau of Economic Research, Bonds Outstanding, Par Value, All Industries for United States [M10083USM311NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M10083USM311NNBR/, July 6, 2015.