These Data Are Year-To-Year Changes In Total Operated Track Mileage As Published In The Above Sources. Data On Increases For The Years 1877-90 And 1917-63, Are For Calendar Years; Those For 1891-1916 Are For Years Ending June 30. Data On Operated Track Mileage Are Compiled By The Interstate Commerce Commission. Data For 1876-90 Are From "Railway Statistics Before 1890," Icc Statement No. 32151 (Mimeographed), 1932. For These Historical Data The Icc Used The Annual"Poor'S Manual Of Railroads." Data For 1891-1954 Are From Icc,"Statistics Of Railways In The United States." Later Data Are From"Transport Statistics In The United States, Part 1." Operated Track Includes Main Tracks, Yard Tracks, And Sidings. The Data Cover Class I, Ii, And Iii Railroads. Prior To 1908 They Also Included Switching And Terminal Companies."Circular" And Unofficial Roads Are Excluded. Alaska And Hawaii Are Included Beginning With Data For 1960. Each Company Reported Its Total Operated Track Mileage; Since Two Companies Might Operate The Same Track, There Is Some Duplication. Data For Different Years Are Often Not Entirely Comparable Because Of Changes In Accounting And Reporting Methods. Source: Interstate Commerce Commission, 1877-1890:"Historical Statistics Of The United States, Colonial Times To 1957, " Bureau Of The Census, Series Q17. 1891-1956: Ibid., Series Q48. 1957-1962: Ibid., "Continuation To 1962 And Revisions, " Bureau Of The Census, February 1965, Series Q48. 1963:"Transport Statistics In The United States, Part 1", Interstate Commerce Commission, Bureau Of Transport Economics And Statistics.
This NBER data series a02083 appears on the NBER website in Chapter 2 at http://www.nber.org/databases/macrohistory/contents/chapter02.html.
NBER Indicator: a02083
Release: NBER Macrohistory Database
National Bureau of Economic Research, Increases In Railroad Track Mileage Operated for United States [A02083USA581NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/A02083USA581NNBR/, November 27, 2015.