Series Is Presented Here As Two Variables--(1)--Original Data, 1913-1937 (2)--Original Data, 1933-1944. Monthly Data Were Available Beginning In 1933. Annual Averages Date To 1913. The 1937 Annual Figure For The Two Variables Has A Ratio Of 1.063 (1937 2Nd Segment Divided By The 1St Segment Yields 877.43/825.31=1.063. Source: Bls Letters For 1933, 1934, 1936, 1937; Bls "Wholesale Prices, " January, 1936, P.17, For 1935; Current Bulletins For 1938 And Succeeding Years.
This NBER data series m04137b appears on the NBER website in Chapter 4 at http://www.nber.org/databases/macrohistory/contents/chapter04.html.
NBER Indicator: m04137b
Release: NBER Macrohistory Database
National Bureau of Economic Research, Wholesale Price of Horse-Drawn Mowers, Composite, F.O.B. Shipping Point for United States [M0437BUSM284NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M0437BUSM284NNBR/, August 2, 2015.