Series Is Presented Here As Two Variables--(1)--Original Data, Percent Expanding, 1948-1957 (2)--Original Data, Cumulative Net Expanding, I.E., The Cumulation Of Differences Between The First Variable And 50 %. Source: National Association Of Purchasing Agents, Business Survey Reports.
This NBER data series m06139b appears on the NBER website in Chapter 6 at http://www.nber.org/databases/macrohistory/contents/chapter06.html.
NBER Indicator: m06139b
Release: NBER Macrohistory Database
National Bureau of Economic Research, Orders, Per Cent Expanding, Cumulative for United States [M0639BUSM156NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M0639BUSM156NNBR/, November 27, 2015.