The Role of Relative Cohort Size and Relative Income in the Demographic Transition

This paper summarizes the results of other analyses by the author with regard to the importance of relative cohort size (RCS) in determining male relative income (the income of young adults relative to prime-age workers) and general patterns of economic growth, and in turn influencing fertility in the currently more-developed nations. It then goes on to demonstrate that these same effects appear to have been operating in all of the one hundred-odd nations which have experienced the fertility transition since 1950. Parameter estimates based on the experience of all 189 countries identified by the United Nations between 1950 and 1995 are used to simulate the effects on fertility of migration from Third to First World countries. This exercise suggests that we get the best of all possible outcomes with migration: population is reduced in “overcrowded” Third World nations, total world population growth is substantially reduced, and scores of children are given the opportunity of growing up with all the educational and health advantages of U.S. residents.