Demographic dimensions in forecasting: Adding education to age and sex

Any breakdown of the total population (i.e., the number of living individuals staying within a well-defined area) for analytical purposes follows a certain implicit or explicit logic. In demography it has become standard practice to sort the total population along the dimensions of age and sex. Although this practice is usually taken for granted and not explicitly justified, it may be useful to recall the good reasons that have lead to this practice. This appraisal of age and sex helps to evaluate the importance one should assign to explicit consideration of such other possible dimensions as marital status, ethnicity, labor force participation, region of origin, and educational status. Three criteria should govern the determination to explicitly consider a particular dimension (breakdown) in demographic analysis in general and in population projections in particular: Criterion 1. To the users the dimension is interesting in its own right and therefore desirable as an explicit output parameter. Criterion 2. The dimension is a relevant source of demographic heterogeneity with an impact on the dynamics of the whole system and therefore on the resulting population size. Criterion 3. It is feasible (in terms of data and methodology) to consider the dimension explicitly. Age meets these criteria...