Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950–2019: a comprehensive demographic analysis for the Global Burden of Disease Study 2019
Level 3 - non-randomized controlled study
Level assigned by design analogy; comprehensive global observational demographic modeling and data synthesis.
OpenAlex W3093298383 · doi:10.1016/s0140-6736(20)30977-6
What was done
Demographic metrics including fertility, mortality, migration, population size, and healthy life expectancy (HALE) were estimated across 204 countries and territories from 1950 to 2019 for the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. Data sources included 8,078 country-years of vital and sample registration, 938 surveys, 349 censuses, and 238 other sources for fertility; 7,417 sources for under-5 mortality; 7,355 sources for adult mortality; and 1,250 censuses and 747 population registry years for migration and population estimates. Spatiotemporal Gaussian process regression (ST-GPR) and Bayesian hierarchical cohort component models were used to synthesize data and generate age-sex-specific estimates with 1,000 draw-level uncertainty intervals (UI).
What was found
Between 2000 and 2019: - Global total fertility rate (TFR) decreased from 2.72 (95% UI 2.66–2.79) to 2.31 (2.17–2.46). In 2019, 102 of 204 countries had a TFR below the replacement level of 2.1. - Global annual livebirths peaked at 139.6 million (133.0–146.9) in 2016 before declining to 135.3 million (127.2–144.1) in 2019. - Global life expectancy at birth rose from 67.2 years (66.8–67.6) to 73.5 years (72.8–74.3), while under-5 deaths fell from 9.6 million (9.1–10.3) to 5.0 million (4.3–6.0). Total global deaths increased from 50.7 million (49.5–51.9) to 56.5 million (53.7–59.2). - Global population grew by 25.7%, from 6.2 billion (6.0–6.3) to 7.7 billion (7.5–8.0). In 2019, 34 countries experienced negative natural population increase, leading to net population decline in 17 of them. - Global HALE increased from 58.6 years (56.1–60.8) to 63.5 years (60.8–66.1), improving in 202 of 204 countries.
Why it matters
This provides a comprehensive global benchmark of demographic shifts, showing that half of all countries are now below replacement-level fertility while global life expectancy and healthy life expectancy continue to rise.
Limits
Estimates rely heavily on complex statistical modeling, interpolation, and relational life tables to fill substantial data gaps in regions lacking complete vital registration or recent census data. Data quality varies widely by country, and the abstract notes reliance on indirect methods such as sibling histories and serosurveillance for adult mortality and HIV-specific mortality corrections.
Cited by
- supports The global fertility rate has dropped from an average of five children per woman in 1950 to 2.2 children per woman today.