AMERICAN ECONOMIC ASSOCIATION The physical volume of capital, of course, increased much more rap ly than population. An estimate of total capital, which takes accoun of land, structures, producers' durable equipment, inventories and net ago. Capital per head of the population approximately tripled e years foreign claims, increased to nearly ten times its size seventy-fiv What has been the increase in the input of all resources per capita? Suppose we combine our indexes of labor input per capita and of cap- Kendricks figures. But other estimates make the long-term decline somewhat les more. For comparison, the following alternatives are of interest: Given Average Kuznets, Standard Hours Dewhurst and Fichlander Actual Hours in Commodity 1869-79 (4) Barger, Actual Hours in Distribution 1869- 894-1903 (6)Kendrick, Actual Hours Line (1)-Long-Term Changes, "Table 7. Figures extended from 1939-48 to 1944-53 on th shuf tiamat s es plimdricd 3. Needendnd Resources, A New Survey Distribution's Place in the American Economy since 1869, Table 5 ine(6)-Supplied by J. w. Kendrick treated with great GRod s stt'sies tim atms me eridatioenau f. y i p.18) Relatives for 1944 (2)÷(1) Land 133 Structures, producers' durable equipment, inventories and net foreign claims. Neither Goldsmith's figur Kuznets' are free of serious difficulties due to weak esses in the statistical sources of capital data an 0 nent. The decline in abor hours is not a reliable indication since casita s often Itiple shifts ch practic have grown or declined