Release: NBER Macrohistory Database
Source: Data For 1915-1919: Pullman Company Files. Data For 1920-July 1938: U.S. Department Of Commerce, Survey Of Current Business, 1920 Annual Supplement And Following Monthly Issues. Data For August 1938-1940: Interstate Commerce Commission, Letter From The Bureau Of Statistics, November 7, 1941.
This NBER data series m03011 appears on the NBER website in Chapter 3 at http://www.nber.org/databases/macrohistory/contents/chapter03.html.
NBER Indicator: m03011
National Bureau of Economic Research, Revenue Passengers Carried by Pullman Company for United States [M03011USM586NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/M03011USM586NNBR, August 18, 2017.