Incredibly useful new indicator from the World Bank: the wealth of nations.
How did they do it? Total wealth is equated to the present value of the consumption stream. The WB also calculated the value of natural resources and capital. The difference between the value of physical stocks and total wealth is attributed to "intangibles", such as human capital and institutions. (Hence, the value added of the publication is not mainly in its estimates of total wealth, but rather in how total wealth is broken up into components.)
Some results: Globally, most wealth is in intangible form (77%); this is followed by capital (18%) and natural resources (5%). Needless to say, most wealth is in the hands of high income countries (which is to be expected given the method of computing total wealth). However in low income countries the share of natural resources is much greater, at 29% (with only a 16% share of capital in total wealth).
Assuming the now wealthy economies started out like today's low income countries, what they were able to do therefore was convert their resource stocks into other forms of assets. Thus the World Bank data gives us a quantitative handle on the issue of "sustainable development" - often mystically restricted to maintaining natural resource flows, neglecting the possibility that these resource flows can be converted into other forms of wealth.