Economist Bryan Caplan has criticized the way scores in each of the three components are bounded between zero and one , so rich countries effectively can not improve their ranking in certain categories , even though there is a lot of scope for economic growth and longevity left , `` This effectively means that a country of immortals with infinite per-capita GDP would get a score of .666 ( lower than South Africa and Tajikistan ) if its population were illiterate and never went to school . '' As a result of that , rich countries effectively can not improve their ranking in certain categories , even though there is a lot of scope for economic growth and longevity left . `` This effectively means that a country of immortals with infinite per-capita GDP would get a score of .666 ( lower than South Africa and Tajikistan ) if its population were illiterate and never went to school . ''