Source: Bls Bulletins, Nos. 270, 300, 315, 334, 396, 418, 445, 464, 495, And Monthly Issues Of United States Bureau Of Labor, "Retail Prices, " Except December, 1931-December, 1932, Which Are From Special Monthly Mimeographed Reports, Not Previously Published For 1913-1934 Data. 1935-1943 Data Are From Mimeographed Release, "Retail Food Prices By Cities." Between August, 1933, And June, 1936, The Bls Collected Several Prices Per Month. If One Of Them Applied To A Date Between The 12Th And The 18Th, It Was Used As Given. In The Cases Of Other Dates The Given Prices Were Averaged. During The Year 1918, Prices For Standard War Flour Were Included (See Bls Bulletin 334, P.10 Footnote). Beginning In June, 1941, Prices Were Quoted In 10 Pound Units. Here They Have Been Converted To Prices Per Pound.
This NBER data series m04020 appears on the NBER website in Chapter 4 at http://www.nber.org/databases/macrohistory/contents/chapter04.html.
NBER Indicator: m04020
Release: NBER Macrohistory Database
National Bureau of Economic Research, Retail Price of Flour, Wheat, White for Minneapolis, MN [M04020US33460M267NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M04020US33460M267NNBR/, October 8, 2015.