Source: Federal Reserve Board, Bulletin Of December 1927, Pp. 826-827, And Successive Issues
This NBER data series m06013 appears on the NBER website in Chapter 6 at http://www.nber.org/databases/macrohistory/contents/chapter06.html.
NBER Indicator: m06013
Release: NBER Macrohistory Database
National Bureau of Economic Research, Index of Wholesale Trade, Groceries Sales for United States [M06013USM331NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M06013USM331NNBR/, November 27, 2015.