# Estimating national intangible wealth

I seem to recall reading about the following research regarding "national intangible wealth" (IIRC):

1. For each country, compute the GDP.
2. Convert the GDP to "total national capital" using an interest rate (e.g., assuming 5% interest, the total national capital of a country with GDP=\$5B will be \$100B), the same(?) interest for all countries.
3. Subtract from the above total national capital all the tangible capital: industry, farms, infrastructure, education of the population - everything you can put a price tag on.
4. The result is the "intangible national capital" - stable non-corrupt government, courts that enforce contracts, work ethics...

I tried to google things like "national intangible wealth" &c, but found nothing reminiscent of the above approach.

Could you please provide a reference? Criticism of the methodology?