Series Is Presented Here As Three Variables--(1)--Seasonally Adjusted Data, 1875-1915 (2)--Seasonally Adjusted Data, 1914-1919 (3)--Seasonally Adjusted Data, 1916-1961. The Data For 1914 Were Computed By NBER By Raising The Figures Of The Preceding Segment Of This Series Bu Multiplying By 1.0248, The Average Relationship Of January-August 1915 Of This Segment To January-August Of The Previous Segment. These Data Were Computed By NBER From Published Percentage Deviations From Normal. Source: Review Of Economic Statistics, April 1923, P.76 For 1915 Data; Thereafter, W.M. Persons, Forecasting Business Cycles, (John Wiley, New York, 1931), Pp. 93-143.
This NBER data series m12004b appears on the NBER website in Chapter 12 at http://www.nber.org/databases/macrohistory/contents/chapter12.html.
NBER Indicator: m12004b
Release: NBER Macrohistory Database
National Bureau of Economic Research, Index of Industrial Production and Trade for United States [M1204BUSM363SNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M1204BUSM363SNBR/, July 3, 2015.