191
for new metals. The series of this appendix are derived
from data generated by the Bureau of Mines showing
apparent consumption of iron and copper for the period
I9OO-I96O. These figures incorporate imports and exports
of metals in all forms, from ore to the metal content
2
of final products. They do not include production
from scrap, and as such represent additions to the
domestic stock of metals in use.
Basic data are in terms of constant 195^ dollars.
They can be converted to physical equivalents by using
the following values and weights:
Item
Unit of Quantity Value/
Measure (l,000) Unit
Iron content
Copper content
long ton U0,0U7.U $ 13-50
short ton 835*5 4^7* ^+0
Attention is directed to Figures 3 and 5* For
these charts, the annual additions to metals in use
were summed for the period I9OO-I96O. Increases in
the stock of metals in use are shown for the period
I92O-I96O. Comparison of the stock of metals in use
relative to GNP is facilitated by the fact that
unemployment rates for 1920 and 1960 differed by less
3
than 0.025 points per year of time span.
2~
See Raw Materials in the United States Economy:
1900-1961, pp. 85-86 for method used in computing imports
and exports of metals by content.
3
See Long Term Economic Growth, I86O-I965, p. 107*