Source: National Bureau of Economic Research  

Release: NBER Macrohistory Database  

Units:  Millions of Dollars, Not Seasonally Adjusted

Frequency:  Monthly

Series Is Presented Here As Two Variables--(1)--Original Data, 1920-1942 (2)--Original Data, 1942-1956. This Variable Was Computed By NBER By Adding Western Union And Postal Telegraph Data. This Variable Ends In 1942, As A New Accounting Classification Was Introduced In 1943 Which Make The Earlier Figures Not Comparable. Source: Data For 1920-May 1934: Interstate Commerce Commission Files. Data For June 1934-1942: Federal Communications Commission, "Operating Data From Monthly Reports Of Telegraph Carriers".

This NBER data series m03019a appears on the NBER website in Chapter 3 at http://www.nber.org/databases/macrohistory/contents/chapter03.html.

NBER Indicator: m03019a