bicoal
Bituminous Coal Production in USA

Description

The bicoal.tons data set is a time series that contains the production of bituminous coal in millions of net tons per year, for the years 1920-1968.
Source
U.S. Bureau of Mines.
The data are also in Tukey, J.W. (1977). Exploratory Data Analysis. Massachusetts: Addison-Wesley Publishing Co.
Package Sdatasets version 6.1.1-7
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