Global demographic shifts: insights from 1800 to 2100 - WID

How has the world’s population transformed over the past two centuries, and what can we expect in the future? The World Inequality Database (WID) now offers extended series on global demographic shifts from 1800 to 2100, with detailed insights into age, gender, and migration patterns. This new data enhances our understanding of the world’s evolving population dynamics, offering a nuanced understanding of how the world is evolving and what lies ahead.

Key findings

The world population has grown at an unprecedented rate over the past two centuries, increasing from approximately 1 billion in 1800 to 8 billion by 2025.
Fertility and mortality have been the main contributors to population growth in most regions. Migration has also played a crucial role in certain areas, particularly North America/Oceania and Europe, and will continue to do so in the future.
By 2100, global population growth is expected to slow significantly, with Sub-Saharan Africa becoming the most populous region, overtaking East Asia and South/Southeast Asia, and leading both working-age and young-age growth.

Sub-Saharan Africa will maintain the highest share of young people, including young females, as the global young-age population declines from 36% in 1800 to 16% by 2100. Meanwhile, the elderly population will rise sharply from 4% to 24%, particularly in East Asia and Europe.
In contrast, regions such as East Asia will see significant total population declines, particularly in the working-age group, and by 2100, only North America/Oceania and Sub-Saharan Africa are projected to maintain positive population growth, with Sub-Saharan Africa driven by natural increase and North America/Oceania largely by migration.

Methodology and data sources

The WID population series currently covers the total population and adult population (20 years and over) for all 33 core territories (24 countries + 9 subregions) over 1820-2023 and 216 core countries over 1950-2023.

World Inequality Database’s population series were extended into two directions:

Population projections for all 216 core countries over the 2024-2100 period based on the latest UN WPP series (World Population Prospects).
Breakdowns by age groups (0- 14, 15-64, 65+) and gender for all 33 core territories 1800-2100 and all 216 core countries 1950-2100, based on WPP series and other historical sources, such as the Federico-Tena World Population Historical Database and International Historical Statistics

To find out more about the new series and variables, read the Technical notes:

“Extending WID Population Series: Projections 2024-2100 & Age/Gender Breakdowns, World Inequality Lab Technical Note”, 2024/12
“World Totals in WID: Core Territories, Core Countries and Core Macro and Distributional Variables, 1820-2023“, World Inequality Lab Technical Note, 2024/02
To know how to use and download the data, refer to the Methodology and Codes Dictionary.