Data From July, 1907 To October, 1910 And Data From 1932-1942 Exclude Switching And Terminal Companies. Data From November, 1910 Through 1931 Includes This Information. Data Covers "Class A" Or "Class I" Roads. 1910-1919 Data Is Computed From Given "Total Operating Expenses" And "Total Operating Revenues." 1907-1909 And 1920-1942 Data Computed By Subtracting The Given Operating Ratio -- I.E., Ratio Of Operating Expenses To Operating Revenues. Data For June, 1918 And August, 1920 Reflect Wage Increases. January, 1921 Operating Ratio Misprinted In The Source As 95.01 Which It Should Be According To The Published Operating Expenses And Operating Revenues. Source: Interstate Commerce Commission Bulletin Of Revenues And Expenses Of Steam Roads In The U.S., No.5 - P.12, No.18 - P.12, No.31 - P.12, For 1907-1909 Data; Computations From Data In Statistics Of Railways, 1921, P. Xcix, For 1910-1919; Operating Revenues And Operating Expenses Of Class I Steam Railways In The U.S. For 1920-1942 Data.
This NBER data series m09046 appears on the NBER website in Chapter 9 at http://www.nber.org/databases/macrohistory/contents/chapter09.html.
NBER Indicator: m09046
Release: NBER Macrohistory Database
National Bureau of Economic Research, Ratio of Net Revenue From Railway Operations To Total Opera- Ting Revenues, Class I Railroads for United States [M09046USM156NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M09046USM156NNBR/, August 31, 2015.