National income is underpinned by a country's wealth--measured comprehensively to include all assets, produced capital, human capital, natural capital and net financial assets--and sustained economic growth over the long term requires investment in this broad portfolio of assets. While a macroeconomic indicator like GDP provides an important measure of economic progress, it does not reflect changes in the underlying asset base, and hence, used alone, may provide misleading signals about the state of the economy. GDP does not reflect depreciation and depletion of assets, whether accumulation...