方法对比

	Demographic Balancing Equation	Dependency Ratio
领域	人口学	人口学
方法族	Process / pipeline	Process / pipeline
起源年份	1976	1956
提出者	Classical demographic accounting identity	Standard demographic practice (United Nations / national statistical offices)
类型	Population accounting identity for change over a period	Ratio summarizing the age structure of economic dependency
开创性文献	Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell. ISBN: 9781557864512	Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell. ISBN: 9781557864512
别名	Balancing Equation of Population Change, Population Accounting Equation, Components of Population Change Identity	Age dependency ratio, Youth and old-age dependency ratio, Total dependency ratio, Bağımlılık Oranı
相关	4	4
摘要	The demographic balancing equation is the fundamental accounting identity of population change: a population at the end of a period equals its size at the start, plus births, minus deaths, plus in-migrants, minus out-migrants. It is the bookkeeping rule that ties together all the components of population dynamics and guarantees internal consistency in population estimates and projections. Because it is an exact identity, it also serves as a powerful estimation tool — any single unknown component, most often net migration, can be recovered as the residual once the others are known.	The age dependency ratio is a simple summary measure of a population's age structure that expresses the number of people in 'dependent' age groups — children and the elderly — relative to those of working age, conventionally per 100 working-age persons. It is split into a youth dependency ratio and an old-age dependency ratio, and it is among the most widely used demographic indicators of the potential economic burden an age structure places on its productive population.