Demographic dividend, dependency ratio and HIV/AIDS in sub-Saharan Africa : theoretical approach and case studies : a report to the United Nations Fund for Population Activities (UNFPA)
Résumé
The study describes changes in the dependency ratio (Population 0-14 and 65+/ Population 15-64) in sub-Saharan Africa since 1950 in an international context, its determinants (fertility, mortality, migration) and possible consequences on economic growth (the demographic dividend). It investigates in particular the effect of HIV/AIDS and HAART on the dependency ratio. Overall, dependency ratios increased in Africa from 1950 to 1985 following mortality decline and fertility increase, then decreased since 1985. HIV/AIDS seems to have had only a marginal effect on dependency ratios. A simulation model indicates that mortality decline from 30 to 70 years of life expectancy could induce a 22% increase in the dependency ratio, a fertility decline from 7 to 2 children per woman could induce a 54% decline in the dependency ratio, and a very severe HIV epidemic with 25% of adults infected (45% of those aged 15-49) a 12% increase, which could be almost entirely reversed by HAART. In 5 cases studies of countries with moderate to severe HIV epidemics, there was no convincing evidence of any effect of HIV on dependency ratios. In empirical regression models, the effect of HIV on the dependency ratio was mild (+0.022 out of a baseline of 0.892) for an average 10% HIV prevalence, an effect consistent with that of the simulation model. In regression models, the effect of dependency ratios on economic growth was mild and negative after 1980. Altogether, the HIV/AIDS epidemic did not seem to have any marked effect on the age structure and on economic growth in Africa.