Spotlights on Health and Rights

Key topics in the Heilbrunn Department of Population and Family Health

Demography

Sex and Dependency Ratios

Sex ratios are determined by the now familiar forces--fertility, mortality, and migration. Migration, in particular, can influence sex ratios and age pyramids in dramatic fashion. The unbalanced sex ratio of the United Arab Emirates (UAE) came about because the UAE brought in thousands of foreigners from Asia and other parts of the Middle East to work in the country's oil fields and construction sites. The majority of these labor migrants were men unaccompanied by their families. The host governments did not want the immigrants to settle permanently and reasoned that the foreigners were less likely to stay if they had families waiting for them back home. The host governments did not want the immigrants to settle permanently and reasoned that the foreigners were less likely to stay if they had families waiting for them back home.

At the very local level, migration can also generate very peculiar age structures. Examine the structure of an Arizona retirement community in 1990. This was one of the earliest retirement communities. The dependency ratio is highly skewed: there are very few individuals of active ages (18-64) for each retired person (65 and above).