Population Decline: Earth Will be Home to 2 Billion Fewer People than Present UN Projections
Wed, April 21, 2021

Population Decline: Earth Will be Home to 2 Billion Fewer People than Present UN Projections


World population in 2100 could be 8.8 billion, two billion fewer people than present United Nations (UN) projections, a new study finds.

Declining population: positive and negative consequences

University of Washington’s director of the Institute for Health Metrics and Evaluation (IHME), Christopher Murray, who is also the lead author of the study, said via Phys.org that the new forecast means good news for the environment with lower carbon emissions and less stress on food production. To those living in sub-Saharan Africa, the forecast means significant economic opportunity.

However, to those living outside Africa, the inverting population pyramid and declining workforces will have negative consequences for their economy. The study concluded that the ideal solutions for high-income nations would be to sustain their economic growths and population levels. For instance, they can highlight social support for families who want kids and have flexible immigration policies as well.

Murray cautioned that in the face of a shrinking population, it presents “real danger” for countries that consider restricting their citizens’ access to reproductive health services. These policies can lead to potentially devastating consequences. He added that women’s rights and freedom must be at the top list of the development agenda being planned by every government.

Children below 5 to decline by over 40%

The researchers also mentioned that to accommodate the older populations, healthcare systems, and social services will have to be overhauled. As life expectancy increases and fertility rate falls, the number of children below five years old is also forecast to decline by over 40% from 681 million in 2017 to 401 million in 2100.

Population ages 80 and above will balloon to 866 million

The study also found that more than a quarter of the world population or 2.37 billion people will be over 65 years old by 2100. Those over 80 years old will grow from 140 million this year to 866 million by 2100 as well. The sharp decline in the proportion and number of the working-age population will likewise present huge challenges in many nations.

IHME professor Stein Emil Vollset noted that societies will be struggling to grow with fewer taxpayers and workers in their country. For example, the number of the working-age population in China will plunge by 62% from 950 million today to more than 350 million by 2100. On the other hand, the active labor force in Nigeria will grow from 86 million to more than 450 million by the end of the century. These shifts are expected to shuffle the hierarchical system in terms of economic power or influence.



Change in geopolitical power

The study reads that China’s GDP will overtake that of the US by 2050 but it will fall back into second place by 2100. The forecast also shows that India’s GDP will grow, earning the third spot while the UK, France, Germany, and Japan will remain among the 10 largest economics in the world. From eighth rank today, Brazil is forecast to fall to 13th, and Russia from the current 10th rank will fall to 14th. Meanwhile, historical powers in Spain and Italy will plummet from the top 15 to 28th and 25th, respectively.

Richard Horton also said in an interview with Phys.org that the world will be multipolar, which means a distribution of power, by the end of the century. This is because China, the United States, Nigeria, and India will have dominant powers. Horton describes it as a radical change in geopolitical power.

In 2015, Nigeria’s population by broad age group was as follows: under 5 years (31.11 million), 5-14 years (48.82 million), 15-24 years (34.32 million), 25-64 years (61.98 million) 65+ years (4.96 million). The statistic is provided by Our World in Data, a scientific online publication that focuses on large global problems.



UN vs. IHME global population projections

Until now, the intergovernmental organization the UN forecasts that the world population will reach 8.5 billion in 2030, 9.7 billion by 2050, and 10.9 billion by 2100. UN enjoys a monopoly in forecasting the global population. The authors said that the difference between their figures to that of the UN centers on fertility rates. The replacement level fertility for a stable population is said to be 2.1 births per woman. Based on UN calculations, it assumes that nations with low fertility rates today will see those rates increase to about 1.8 kids per woman.

However, Murray said that their IHME analysis shows that as women have access to reproductive health services and become more educated, they choose to have less than 1.5 kids on average.

The IHME is now a global reference for health statistics. It was founded in 2007 and supported by the Bill & Melinda Gates Foundation.



World population: yearly change

Real-time world statistics platform Worldometer also shares the life expectancy at birth this year is 70.8 years for males and 75.6 years for females. In 2015, life expectancy at birth was 69.9 years for males and 74.7 years for females. About 56% or 4.3 billion of the population this year live in urban areas while 44% or 3.4 billion live in rural areas.

Not all countries view a shrinking population the same way. For poorer countries, it is good news because it could spell better living standards. Women will have better education and career opportunities, lower child mortality rates, and access to abortion and contraception. However, in nations where fertility rates are already falling, shrinking it further will cause problems, reports BBC. These countries are the ones that need to work out how they can care for a growing population with fewer people to work and to pay into their system.

To some countries, a shrinking population may mean waiting a lot longer for retirement. They may also strain their healthcare system with more concerns for the aging population. The third thing to consider is migration. Governments may have to open their borders. Thus, the world may become more ethnically and culturally mixed.

When governments try to increase or restrict the birth rate of a country, it usually becomes coercive. This was observed in Scandinavian countries, where birth rates are higher because of incentives like generous childcare and maternity leave. On the other hand, in countries with a high cost of living, some women and men may choose to have fewer kids because they cannot afford more. 

With the possibility that fertility, mortality, and migration patterns will change, the recent IHME analysis serves as a timely warning for the world.