Data Are Smoothed By Macaulay'S Forty-Three Term Graduation (See Measuring Business Cycles By Burns And Mitchell, Chapter Eight). Source: F.R. Macaulay, The Movements Of Interest Rates, Bond Yields, And Stock Prices, NBER No. 33, 1938, Table 21, Col. 2.
This NBER data series m13001a appears on the NBER website in Chapter 13 at http://www.nber.org/databases/macrohistory/contents/chapter13.html.
NBER Indicator: m13001a
Release: NBER Macrohistory Database
National Bureau of Economic Research, Call Money Rates for United States [M1301AUSM156NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M1301AUSM156NNBR, February 9, 2016.