Series Is Presented Here As Two Variables--(1)--Original Data, 1895-1928 (2)--Original Data, 1920-1941. Data Are For The Joplin District, Also Known As The Tri-State District. This Area Includes Parts Of Missouri, Kansas And Oklahoma And Produces About Two-Thirds Of The Ore Mined In The United States. Data For 1920-1935 Are Computed By NBER By Dividing The Original Published Figures By The Number Of Weeks Ending On Saturdays Within The Month. Data Beginning January 1936 Were Computed By Dividing The Original Published Monthly Figures By The Number Of Weeks Ending In Saturday Which Ended Through The Third Of The Next Month. Source: U.S. Department Of Commerce, Data For 1920-1923: Record Book Of Business Statistics. Data For 1924-1941: Survey Of Current Business, Succesive Issues.
This NBER data series m01141b appears on the NBER website in Chapter 1 at http://www.nber.org/databases/macrohistory/contents/chapter01.html.
NBER Indicator: m01141b
Release: NBER Macrohistory Database
National Bureau of Economic Research, Zinc Ore Shipments, Joplin District for Joplin, MO [M0141BUS27900M526NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M0141BUS27900M526NNBR/, August 31, 2015.