More than 20 countries, including Italy, Japan, Poland, Portugal, South Korea, Spain and Thailand, will see their numbers decrease by at least half by 2100, according to projections from ‘a major study.
The Chinese population will increase from 1.4 billion people today to 730 million in 80 years, said the study conducted by an international team of researchers, published Wednesday in The Lancet.
The earth will be home to 8.8 billion people in 2100, two billion less than current UN projections, according to the study, predicting new global energy alignments shaped by falling fertility rates and the Aging of the population.
By the end of the century, 183 of 195 countries, unless there is an influx of immigrants, will have fallen below the replacement threshold necessary to maintain population levels, he said.
Sub-Saharan Africa, on the other hand, will triple to reach some three billion people, Nigeria alone reaching nearly 800 million in 2100, just behind 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 significant economic opportunities for parts of sub-Saharan Africa,” said l lead author Christopher Murray, director of the Institute for Health Metrics Evaluation (IHME) at the University of Washington, said the AFP news agency.
“However, most countries outside Africa will see their numbers shrink and reverse the age pyramids, which will have profound negative consequences for the economy. ”
For high-income countries in this category, the best solutions for maintaining population levels and economic growth will be flexible immigration policies and social support for families who want children, the study concludes.
“However, in the face of declining populations, there is a very real danger that some countries may consider policies that restrict access to reproductive health services, with potentially devastating consequences,” warned Murray.
“It is imperative that women’s freedom and rights be at the top of each government’s development agenda. ”
Social services and health systems will need to be overhauled to adapt to much older populations.
As fertility declines and life expectancy increases worldwide, the number of children under the age of five is expected to decrease by more than 40%, from 681 million in 2017 to 401 million in 2100, 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 years of age. The number of those over 80 will soar from around 140 million today to 866 million.
The sharp decline in the number and proportion of the working age population will also pose enormous challenges in many countries.
“Companies will find it difficult to grow with fewer workers and fewer taxpayers,” said Stein Emil Vollset, professor at IHME.
The number of people of working age in China, for example, will drop from around 950 million today to just over 350 million by the end of the century – a drop of 62%.
The decline in India should be less pronounced, going from 762 to 578 million.
In Nigeria, on the other hand, the active workforce will increase from 86 million today to more than 450 million in 2100.
These tectonic changes will also reshape the hierarchical order in terms of economic weight, predict the researchers.
By 2050, China’s gross domestic product will exceed that of the United States, but will fall to second place by 2100, they predict.
India’s GDP will increase to take third place, while France, Germany, Japan and the United Kingdom will remain among the 10 largest economies in the world.
Brazil is expected to drop from eighth to 13th today, and Russia from 10th to 14th. The historic powers, Italy and Spain, meanwhile, go from the top 15 to 25 and 28 respectively.
Indonesia could become the 12th largest economy in the world, while Nigeria – currently 28th – should be in the top 10.
“By the end of the century, the world will be multipolar, with India, Nigeria, China and the United States being the dominant powers,” said Richard Horton, describing the study as describing “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 the projection of the world population.
The difference between the UN and the IHME figures depends mainly on fertility rates. The so-called “replacement rate” for a stable population is 2.1 births per woman.
UN calculations assume that low-fertility countries today will see these rates rise, on average, to around 1.8 children per woman over time, said Murray.
“Our analysis suggests that when women become more educated and have access to reproductive health services, they choose to have fewer than 1.5 children on average,” he said by email.
“Continued global population growth over the century is no longer the most likely trajectory for the world’s population. ”
Founded in 2007 and supported by the Bill and Melinda Gates Foundation, the IHME has become a global benchmark for health statistics, particularly its annual reports on the global burden of disease.