Le ble en herbe
Population ageing is a shift in the distribution of a country's population towards older ages. This is usually reflected in an increase in the population's mean and median ages, a decline in the proportion of the population composed of children, and a rise in the proportion of the population that is elderly. Population ageing is widespread across the world. It is most advanced in the most highly developed countries. Mauritius had a population of 1,260,403 in 2007, with the number of people aged 60 and above amounting to 126,080. However, it has been estimated that by 2047, the number will rise to 362,700, since life expectancy will be 74.23 for males and 79.33 for females.
Population ageing arises from two demographic effects: increasing longevity and declining fertility. An increase in longevity rises the average age of the population by increasing the numbers of surviving older people. A decline in fertility reduces the number of babies, and as the effect continues, the numbers of younger people in general also reduce.
Declining fertility is the largest contributor to population ageing in the world today. More specifically, it is the large decline in the overall fertility rate over the last half century that is primarily responsible for the population ageing in the world’s most developed countries. Because many developing countries are going through faster fertility transitions, they will experience even faster population ageing than the currently developed countries in the future.
The rate of population aging may also be modulated by migration. Immigration usually slows down population ageing because immigrants tend to be younger and have more children. On the other hand, emigration of working-age adults accelerates population ageing, as it is observed now in some Caribbean nations. Population ageing in these countries is also accelerated by immigration of elderly retirees from other countries, and