ABSTRACT
The previous chapters provide expert views on fertility, mortality, and migration. This chapter presents a synthesis of the expert views and, based on this synthesis, two sets of alternative scenario projections: one set in which the fertility, mortality, and migration components are assumed to be deterministic, independent of one another, and not subjected to any feedbacks; and another set in which certain consistent “stories” are defined and the components interact and react to certain outcomes of the projections such as population growth and aging. These two sets correspond to the two different meanings of “scenario” used in population projections (as discussed in Section 2.6). In Section 15.2 all possible combinations of the high, central, and low assumptions in fertility, mortality, and migration are presented. Section 15.3 provides three examples of interaction scenarios.
