Volume 48 - Article 13 | Pages 353–372  

World population aging as a function of period demographic conditions

By Fernando Fernandes, Cássio M. Turra, Eduardo L.G. Rios Neto

Abstract

Background: Population aging is a fundamental element of the demographic transition. In the absence of births, deaths, and migration, the mean age of any population will increase one year per calendar year. The intensity of period birth, death, and migration conditions (i.e., their crude rates and the difference between their mean age and the mean age of the population) either lessen or strengthen this natural tendency of populations to age.

Objective: We investigate the contribution of births, deaths, and migration to population aging across the globe from 1950 to 2100. We examine whether a concerted pattern of population aging is associated with changes in period demographic conditions.

Methods: We apply a mathematical expression proposed by Preston, Himes, and Eggers (1989) that decomposes the rate of change in the mean age of a population according to period demographic conditions. We use the 2022 revision of the United Nations population estimates and projections covering 236 countries or areas.

Results: During the demographic transition, population aging follows a general concerted pattern characterized by five distinct stages. Populations age because of declining inflows (births) at age zero and insufficient outflows (deaths) at older ages. Overall, migration does not play a pivotal role but can be more relevant in specific countries or regions.

Contribution: Our study combines long-time series data for most countries in the world with an elegant mathematical solution proposed by Preston, Himes, and Eggers (1989) to empirically measure the dynamics of population aging according to period demographic conditions.

Author's Affiliation

• Fernando Fernandes - Universidade Federal de Minas Gerais (UFMG), Brazil EMAIL
• Cássio M. Turra - Universidade Federal de Minas Gerais (UFMG), Brazil EMAIL
• Eduardo L.G. Rios Neto - Universidade Federal de Minas Gerais (UFMG), Brazil EMAIL

Other articles by the same author/authors in Demographic Research

Age reporting for the oldest old in the Brazilian COVID-19 vaccination database: What can we learn from it?
Volume 48 - Article 28

Assessing the quality of education reporting in Brazilian censuses
Volume 42 - Article 15

Mortality selection among adults in Brazil: The survival advantage of Air Force officers
Volume 37 - Article 41

Age, education, and earnings in the course of Brazilian development: Does composition matter?
Volume 28 - Article 20

The number of centenarians in Brazil: Indirect estimates based on death certificates
Volume 20 - Article 20

Most recent similar articles in Demographic Research

Ageing and diversity: Inequalities in longevity and health in low-mortality countries
Volume 50 - Article 12    | Keywords: aging, health, lifespan inequality, longevity, old-age threshold, regional differences, socioeconomic status

Fertility decline, changes in age structure, and the potential for demographic dividends: A global analysis
Volume 50 - Article 9    | Keywords: age structure, demographic dividend, demographic transition, fertility, migration, population momentum, working-age population

Geographic proximity to siblings in older adulthood
Volume 49 - Article 7    | Keywords: geographical proximity, older adults, population, register data, Sweden

Frailty at death: An examination of multiple causes of death in four low mortality countries in 2017
Volume 49 - Article 2    | Keywords: aging, causes of mortality, mortality, multiple causes of death

How does the demographic transition affect kinship networks?
Volume 48 - Article 32    | Keywords: demographic transition, demographically dense ages, kinship network, net reproductive rate, time-invariant model