By Pierre Buhler – Khaleej Times
The latest United Nations population figures provide a dramatic glimpse of how the demographic map of the planet is being reshaped. For the latest revision of its biennial “World Population Prospects,” the UN Population Division has extended its forecasts by 50 years, to 2100. Long-term forecasts must be taken with a grain of salt – they “have no operational role,” as the French demographer Herva Le Bras has written; they just help “staging and exaggerating today’s fears.”
Still, the margins of error allow for a fairly reliable picture of the world’s population in the decades to come. And what matters more is the breakdown of the aggregate figures, as their distribution holds far-reaching consequences.
For this, demography delivers a high level of certainty. The women liable to give birth within a generation are already born; life expectancy and mortality indexes evolve slowly. The most volatile factor is actually the fertility rate – the number of children per woman. Only if this rate is above the generation replacement level of 2.1 will there be a natural increase of a population. When it hovers between 5 and 7, as it does in some 20 countries, the “compounded interest” effect is extremely powerful.
Pierre Buhler is a former French diplomat and associate professor at Sciences Po, Paris,
For full article:
No comments:
Post a Comment