Although there are more and more people on earth, in the long term the world population will most likely shrink again. According to a new analysis, the vast majority of countries in the world will likely be faced with very low birth rates by the end of the century.

A renowned team of experts estimates in the journal “The Lancet” that in the year 2100 only six countries worldwide – Samoa, Tonga, Somalia, Niger, Chad, Tajikistan – will have above the mark of 2.1 children per woman. This value is generally considered a threshold for keeping the population at a constant level through births in the long term.

For the remaining 198 countries, the researchers assume that the birth rate in 2100 will be below the 2.1 mark. The number of people there is likely to decline in the long term unless countermeasures are taken through immigration, writes the team led by the Institute for Health Metrics and Evaluation (IHME) at the US University of Washington in Seattle. According to the forecast, 155 countries will already be below the 2.1 threshold in 2050 (2021: 110).

“We are facing a shocking social change in the 21st century,” said IMHE researcher Stein Emil Vollset, according to the statement. The world will simultaneously be faced with a baby boom in some countries and a shortage of young talent in many others. Co-author Natalia Bhattacharjee adds: The development will “completely reshape the global economy and the international balance of power and require a reorganization of societies.” There will be fierce competition for migrants to maintain economic growth.

Predictions are subject to uncertainty

For Catherina Hinz, executive director at the Berlin Institute for Population and Development, the new report confirms the trend also adopted by other institutions. However, she points out that such estimates should be treated with caution. “Projections that go more than 25 years into the future are super uncertain,” Hinz, who was not involved in the report, told the German Press Agency. After all, no one can predict with absolute certainty how the economy, society and health will develop in the world’s regions.

Between 1950 and 2021, the global birth rate fell from around 5 to 2.2, and by the end of the century it will be 1.6, the team led by IHME researchers now predicts in the Lancet. For comparison: the United Nations (UN) estimates were slightly less drastic at around 1.8 in a 2022 report. At that time, the UN assumed that the world population would peak at 10.4 billion people in the 2080s. It is currently assumed that there are around 8.1 billion people.

For Western Europe, the Lancet report funded by the Bill and Melinda Gates Foundation predicts an average birth rate of 1.37 in 2100. For Germany, the Federal Institute for Population Research announced that the birth rate in Germany has fallen significantly over the past two years, from 1.57 children per woman in 2021 to around 1.36 in autumn 2023. According to the Federal Institute, the decline could be due to the global one crises currently lie.

What to do if there are few young people?

The Lancet report predicts a birth rate of less than 1 in 13 countries in 2100, including South Korea, Taiwan and Bosnia and Herzegovina. According to demography expert Hinz, governments in countries that will have low birth rates in the future face questions such as: How do you keep the economy going in the face of a shrinking population? What role should immigration play? And how should it be organized? How are fewer young people supposed to finance more senior citizens? “Politicians must pay more attention to demographic developments when planning for the future.”

In principle, Hinz sees the falling birth rates around the world as positive. Such a decline is usually an indication of longer life expectancy and more education for women. In other words: “Improvements in living conditions go hand in hand with falling numbers of children.”

In some places the population continues to grow

According to the Lancet report, there will continue to be comparatively high birth rates, especially in countries south of the Sahara. In these states – many of them politically and economically unstable, heat-stressed and with ailing health systems – the population is expected to continue to grow over the course of the 21st century.

The research team assumes that in around 75 years, more than half of all babies born worldwide will be born in sub-Saharan Africa. “This makes it clear that access to modern contraceptives and women’s education urgently need to be improved in these countries,” the team wrote in a statement.

The researchers used data from the 2021 “Global Burden of Disease” report as the basis for their forecasts. For their estimates, they made predictions on, among other things, mortality, birth rates, education levels, lack of contraceptive options, child mortality and urbanization.

The German expert Hinz assumes that the general trend in birth rates will continue. Future crises such as wars and climate-related disasters could temporarily slow down development. “But the big tanker world population is difficult to get out of the way.”