In early years, aquot;productionaquot; was used loosely; later, it was superseded by a more precise statement of the means of ... Indexes were constructed by combining data on physical output aquot;of as many minerals as possible, aquot; with values as ... See also series G 154-155 which give total production, bituminous and anthracite combined, and tonnage per man-hour. G 13-15. Bituminous coal: Production, 1807-1945;anbsp;...
|Title||:||Historical statistics of the United States, 1789-1945|
|Author||:||United States. Bureau of the Census, Social Science Research Council (U.S.)|
|Publisher||:||united states bureau of the census. - 1949|