Population Momentum from Migration

Population Momentum from Migration Josh Goldstein University of California, Berkeley Abstract: The study of population momentum has focused on changing birth rates, but it is also possible to reach a stationary population through migration. In this talk, I’ll show the momentum implied by a change in migration regimes. I will investigate the eventual stationary population size implied by migration-change as opposed to fertility-change, and the differences in age-structure. A simple model is used which has two key simplifying assumptions: (1) all migrants enter (or leave) at the same age, an age that is prior to childbearing and (2) the number of migrants who enter (or leave) is a constant proportional to the current population size. According to this model, stationary-through migration populations will be closer to their original pre-transition size (have less momentum) than stationary-through-fertility populations and will have an age structure that has less dependency. We can discuss the realism of this model and its potential applicability to the contemporary world. About the presenters: Josh Goldstein is Chancellor’s Professor of Demography at the University of California, Berkeley. He received his PhD from Berkeley and has held positions at Princeton and MPIDR. His research interests include formal demography, mortality, fertility and historical demography.