ABSTRACT
All population projections require the computations of survivors. Sometimes, moreover, the entire projection is reduced to this computation, because the cohorts that are of interest are all already born at the base date of the projections. The chapter examines the model life tables of the United Nations in their form adapted for computation of survivors. The projective probability constitutes the type of index that allows the application of a given mortality in a population, in order to determine the deaths in the different cohorts or groups of cohorts and, by subtraction, to deduce the survivors at projected dates. For the mortality of a population, it is customary to take the continuation of a previously observed rate of decline as the possible pace of the decline.
