Certainty and uncertainty in demographic forecasting

Demographic forecasting may rely on a simple extrapolation of the trends in total population or in the annual rate of growth, preferably by referring to a general law for a population's evolution. But the most commonly used method today is the ‘Component’ method, which projects the population distributed by age and sex by means of specific mortality rates; the annual number of births is derived from the age-specific fertility rates. The weight of the fertility assumptions in the projection becomes more and more important as the duration increases, but the method insures an internal coherence of the results. To cite this article: H. Le´ridon, C. R. Geoscience 335 (2003). [Copyright &y& Elsevier]