By 2064, the world’s population is estimated to reach 9.7 billion people. By 2100, however, we will be ‘only’ 8.8 billion souls on the planet. This is shown by a comprehensive analysis, published in the journal The Lancet. The findings are somewhat surprising. For example, a United Nations report last year suggested that the world’s population would be 10.88 billion people by the year 2100. The new estimates are as much as 2 billion heads fewer.

According to the researchers, it can be traced, among other things, to the unprecedented rate at which fertility rates (the average number of children born per woman) in sub-Saharan Africa are declining.

Maximum size

All in all, the researchers therefore expect the world’s population to reach its maximum size quite quickly. As early as 2064, 9.7 billion people would be the peak. In the following decades, the number of people on Earth will decrease, and then by 2100 the world’s population would fall to 8.8 billion people.

Global fertility rates are expected to decline sharply over the next century. Whereas on average every woman had 2.37 children in 2017, that number will have fallen to 1.66 by 2100. That’s far less than the minimum 2.1 children needed to keep population numbers stable.

We will see a decrease in individual countries and in some countries, the fertility rates will drop well below the global average. For example, the researchers expect that by 2100, on average, only 1.2 children will be born per woman in Italy and Spain. And Poland would even see the fertility rate fall to 1.17 by the end of this century.

Sub-Saharan Africa

And in sub-Saharan Africa, the fertility rate is expected to decrease. And strongly, too. Whereas women in this part of the world still have an average of 4.6 children in 2017, we are expected to see women have an average of 1.7 children by the year 2100. And in a country like Niger – which recorded the world’s highest fertility rate in 2017, which is, on average, 7 children per woman – there will be a significant decline. By 2100, researchers expect only 1.8 children per woman to be born in the country.

First, a period of growth

Although fertility rates in Africa – partly because of the increasing availability of contraceptives and more and more girls having access to education – are declining, the population will continue to grow strongly in the coming decades. For example, the number of people in sub-Saharan Africa is expected to triple in the coming decades, reaching 3.07 billion in 2100. This can be partly traced to the fact that more and more girls are reaching childbearing age. In addition, mortality rates are falling. The population is also growing in North Africa and the Middle East. And along with sub-Saharan Africa, these are the only regions expected to host a larger number of people by 2100 than in 2017.

Then a period of decline

While the populations in the areas mentioned above continue to grow for a while, there will be shrinkage in many other places. In Asia in particular and the central and eastern part of Europe, populations are rapidly shrinking. And 23 countries can even expect their population to be 50% smaller than they are today by the year 2100. This is true, for example, for Japan (which is expected to go from 128 million people in 2017 to 60 million people in 2100). But also for Thailand, Spain, Italy, Portugal and South Korea. Another 34 countries are expected to see their populations decrease by 25 to 50 percent. This is true, for example, of China, which had a population of 1.4 billion in 2017, but will fall to 732 million people by 2100.

New ranking

The ranking of countries by the number of inhabitants will therefore change dramatically in the coming decades. Currently, China leads the list. But it will fall back to third position in 2100, with India (with a population of just over 1 billion) and Nigeria (with about 791 million inhabitants) leading the pack. The US (now third in the rankings) will fall back to fourth place, while the Democratic Republic of Congo – now in 18th place – will advance to sixth place. “In the 21st century, there will a revolution in the history of our human civilization,” says Dr. Richard Horton, editor-in-chief of The Lancet. “Africa and the Arab world will shape our future, while the influence of Europe and Asia diminishes. By the end of the century, the world will be multipolar, with India, Nigeria, China and the US as the dominant powers. This will really be a whole new world, one that we have to prepare for now.”

Cassidy Perry

Cassidy is a certified dietician with a focus on patients suffering with diabetes. She has more than 10 years of experience, working with patients of different background. She writes health-related article for the Scientific Origin.