The world population passed 1 billion for the first time in history in the first half
of the 19th century. Since then, the global population has continued to grow, and
most regions and countries are experiencing rapid and broad demographic change. In
2022, the world population reached about 7.9 billion people, and according to the
current projections developed by the United Nations, it could grow to approximately
9.7 billion in 2050. Until the middle of the 21st century, population growth rates
will differ by region, and Central and Southeast Asia will be the most populated areas.
A high increase in population is also expected to occur in sub-Saharan Africa, whereas
Europe will reach a population peak during the 2030s, with the European population
declining until 2050 owing to a low fertility level. With declines in fertility, the
world’s population is ageing. In 2018, the number of persons in the world aged 65
and over was higher than the number of children under five for the first time. All
regions will experience ageing, with faster progress in developing countries than
has historically been observed in developed regions. The projected trends in the world
population are a common result of population momentum, future levels of fertility
and mortality, and regional migration flows. The contribution of these components
to future population trends will vary by region and country.