Glenn Reynolds notes a good one this morning in Reason by Ronald Bailey:

For the average American living in the United States is like having more than half a million dollars in wealth. So says a new study from the World Bank, Where is the Wealth of Nations?: Measuring Capital for the 21st Century, which makes estimates of the contribution of natural, produced, and intangible capital to the aggregate wealth of 120 countries.

Why are Americans so well off? It’s not just because of America’s fruited plains and its alabaster cities. In fact, it turns out that such natural and man-made resources comprise a relatively small percentage of our wealth.

The World Bank study begins by defining natural capital as the sum of nonrenewable resources (including oil, natural gas, coal, and mineral resources), cropland, pastureland, forested areas, and protected areas. Produced capital is what many of us think of when we think of capital. It is the sum of machinery, equipment, and structures (including infrastructure) and urban land. The Bank then identifies intangible capital as the difference between total wealth and all produced and natural capital. Intangible capital encompasses raw labor; human capital, which includes the sum of the knowledge, skills, and know-how possessed by population; as well as the level of trust in a society and the quality of its formal and informal social institutions.