More than 20 countries, including Italy, Japan, Poland, Portugal, South Korea, Spain and Thailand, will see their number decrease by at least half by 2100, according to projections from a major study.
China’s population will drop from 1.4 billion people today to 730 million in 80 years, said the study led by an international team of researchers, published in The Lancet on Wednesday.
Earth will house 8.8 billion people by 2100, two billion fewer than current UN projections, according to the study, anticipating new global power alignments shaped by declining fertility rates and aging populations.
By the end of the century, 183 of 195 countries, except for an influx of immigrants, will have fallen below the replacement threshold necessary to maintain population levels, he said.
Meanwhile, Sub-Saharan Africa will triple to some three billion people, with Nigeria only expanding to almost 800 million in 2100, second only to India’s 1.1 billion.
‘Good news for the environment’
“These forecasts suggest good news for the environment, with less stress on food production systems and lower carbon emissions, as well as a major economic opportunity for parts of sub-Saharan Africa,” said lead author Christopher Murray, director of the Institute. of Health Metrics and Assessment (IHME) at the University of Washington, he told the AFP news agency.
“However, most countries outside of Africa will see a reduction in the workforce and inversion of population pyramids, which will have profound negative consequences for the economy.”
For high-income countries in this category, the best solutions to maintain population levels and economic growth will be flexible immigration policies and social support for families who want to have children, the study concluded.
“However, in the face of population decline, there is a very real danger that some countries will consider policies that restrict access to reproductive health services, with potentially devastating consequences,” Murray said.
“It is imperative that women’s freedom and rights be at the top of every government’s development agenda.”
Social services and health systems will need to be revised to accommodate much older populations.
As fertility declines and life expectancy increases worldwide, the number of children under the age of five is forecast to decrease by more than 40 percent, from 681 million in 2017 to 401 million in 2,100, according to the study. .
At the other end of the spectrum, 2.37 billion people, more than a quarter of the world’s population, will be over 65 by then. The number of people over 80 will increase from about 140 million today to 866 million.
Sharp falls in the number and proportion of the working-age population will also pose enormous challenges in many countries.
“Societies will fight to grow with fewer workers and taxpayers,” said Stein Emil Vollset, professor at IHME.
The number of people of working age in China, for example, will drop from about 950 million today to just over 350 million by the end of the century, a drop of 62 percent.
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The decline in India is expected to be less pronounced, from 762 to 578 million.
In Nigeria, by contrast, the active workforce will expand from 86 million today to more than 450 million in 2100.
Economic forecast
According to the researchers, these tectonic changes will also reorganize the hierarchical order in terms of economic influence.
By 2050, China’s gross domestic product will exceed that of the United States, but they forecast it will return to second place by 2100.
India’s GDP will rise to number three, while France, Germany, Japan and the United Kingdom will remain among the 10 largest economies in the world.
Brazil is projected to fall in the ranking from the eighth today to 13 and Russia from 10 to 14. The historical powers of Italy and Spain, meanwhile, decrease from the top 15 to 25 and 28, respectively.
Indonesia could become the twelfth largest economy in the world, while Nigeria, currently ranked 28th, is projected to rank first.
“By the end of the century, the world will be multipolar, with India, Nigeria, China and the United States as dominant powers,” said Richard Horton, describing the study as a description of “radical changes in geopolitical power.”
Until now, the UN, which forecasts 8.5, 9.7, and 10.9 billion people in 2030, 2050, and 2100, respectively, had a virtual monopoly on projected world population.
The difference between the UN and IHME figures depends on fertility rates. The so-called “replacement rate” for a stable population is 2.1 births per woman.
UN calculations assume that countries with low fertility today will see those rates increase, on average, to about 1.8 children per woman over time, Murray said.
“Our analysis suggests that as women become more educated and have access to reproductive health services, they choose to have fewer than 1.5 children on average,” she explained by email.
“The continued growth of world population during the century is no longer the most likely path for world population.”
Founded in 2007 and supported by the Bill and Melinda Gates Foundation, IHME had become a global benchmark for health statistics, especially its annual Global Burden of Disease reports.
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