Papua New Guinea gives in this study the unique example of a full leftward shift, which as might be expected, causes increasing disparities. The disparity index for Papua New Guinea has increased by this shift between 1972 and 1980 from 38 to 44 percent. Province Share of Pop. HDI 1972 Share of Pop. High HD suggests potentially limited disparities.
Development is achieved by reducing urban-rural and regional differences to acceptable levels.
What remains are ethnical, economic and gender disparities. They are, for example, all observed in USA, however, in a much moderate range than in South Africa at the medium level of development. Other disparities or problems which are existent in many of the top ranking countries, are not reflected to their HDI's yet. Well known problems are crime and drug abuse, besides the so called migrant, guest workers who are potential minorities of these countries are still statistically not members of respective countries. As HD progresses the disaggregation stresses at each level a different problem with respect to gender.