Source: Data For 1919-1935: S. Fabricant, Capital Consumption And Adjustment (NBER), 1938, Table 29, Pp. 160-161; Data For 1936-1939: NBER Estimates
This NBER data series a10066 appears on the NBER website in Chapter 10 at http://www.nber.org/databases/macrohistory/contents/chapter10.html.
NBER Indicator: a10066
Release: NBER Macrohistory Database
National Bureau of Economic Research, Repairs and Maintenance, Business Capital, Public Utilities for United States [A10066USA027NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/A10066USA027NNBR/, July 4, 2015.