The Gap: Concept, Measurement, Trends

By rich nations we presumably mean those that command a volume of economic goods that, relative to population, is significantly larger than some acceptable level. By analogy those nations are poor whose command of economic goods, on a per capita basis, is so much below that acceptable level as to imply major shortcomings and deprivation. This command over goods may be approximated by the stock of material assets, preferably supplemented by some valuation of the human resources at the nation’s disposal. But the effective magnitude of such productive assets is best revealed by the annual output which they, in fact, serve to produce. Despite several vexing problems of definition and interpretation, the long-term level of per capita national product is still a reasonable criterion of the wealth and poverty of nations — long-term meaning periods long enough to obviate distortion by transient disturbances and fluctuations.