.BG D
.FN bicoal
.TL
Bituminous Coal Production in USA
.PP
.AG tons
time-series giving production of
bituminous coal in millions of net tons per year, 1920-1968.
.SH SOURCE
U. S. Bureau of Mines, also in
J. W. Tukey,
.ul
Exploratory Data Analysis,
1977, Addison-Wesley Publishing Co., Massachusetts.
.KW dataset
.WR
