Source: Interstate Commerce Commission, Computed By NBER
This NBER data series m09045 appears on the NBER website in Chapter 9 at http://www.nber.org/databases/macrohistory/contents/chapter09.html.
NBER Indicator: m09045
Release: NBER Macrohistory Database
National Bureau of Economic Research, Net Railroad Operating Income, Class I Railroads, for United States [M09045USM144SNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M09045USM144SNBR/, November 30, 2015.