ABSTRACT

It is readily seen that we may apply some observed fertility and mortality patterns to a population whose present structure is known, and that this would permit determination of the new structure of the population for each of the years to come. Some projective computations that would be carried out on the total of a population can only be managed on the basis of indices of gross measurement, and would not permit arriving at actual forecasts, if these are felt to be necessary. Population projections may concern geographic areas in which migratory movements have a decisive influence upon demographic development. This is the case in urban areas, and any projection of the population of the city that would be a forecast cannot hope to free itself of hypotheses concerning migration.