Natural increase, and net international migration are the demographic
processes that determine the amount of growth or decline in a nation's
population. In a country such as the United States, the contribution
of net international migration to overall population change overshadow
s the contribution of natural increase. It has long been the practice,
however, when making population projections for countries, to conside
r the role of zero net international migration in an incorrect manner.
Some analysts have assumed that if the same number of people leave an
d enter the country each year, then the effect of net international mi
gration will be zero. This article examines that assumption and shows
that it is fallacious. Examining the direct, indirect, total, and nega
tive demographic impacts of zero net international migration through s
imulations with demographic data, we demonstrate that zero net interna
tional migration is not the same and therefore does not have the same
demographic results and implications as zero international migration.
We conclude that zero net international migration should not be confus
ed with zero international migration. In discussions of international
migration in either sending or receiving countries, the two concepts m
ust be kept separate for they are not identical and, moreover, have de
cidedly different demographic implications and effects.