A population projection, in the field of

demography Demography () is the statistical study of human populations: their size, composition (e.g., ethnic group, age), and how they change through the interplay of fertility (births), mortality (deaths), and migration. Demographic analysis examine ...

, is an

estimate Estimation (or estimating) is the process of finding an estimate or approximation, which is a value that is usable for some purpose even if input data may be incomplete, uncertain, or unstable. The value is nonetheless usable because it is de ...

of a future

population Population is a set of humans or other organisms in a given region or area. Governments conduct a census to quantify the resident population size within a given jurisdiction. The term is also applied to non-human animals, microorganisms, and pl ...

. It is usually based on current population estimates derived from the most recent census plus a projection of possible changes based on assumptions of future births, deaths, and any migration into or out of the region being studied. Population projections are used by businesses, governments, and other program planners to assess future demand for consumer products, basic resources such as energy, water, and food, as well as services such as childcare, education, and care for the elderly. Governments and organizations make population projections for their own countries. In addition, organizations like the Population Division of the United Nations Department of Economic and Social Affairs, the

US Census Bureau The United States Census Bureau, officially the Bureau of the Census, is a principal agency of the U.S. federal statistical system, responsible for producing data about the American people and economy. The U.S. Census Bureau is part of the U ...

, and The Population Reference Bureau, develop their own projections. To make these projections they make assumptions about future values of fertility, mortality, and migration. Different assumptions about the future produce different results for future population changes, and these assumptions, about an unknowable future, although produced by experts based on research conducted by themselves and others, may be wrong and produce results that are also wrong.

References

Demography {{statistics-stub

See also

References