A new study published in The Lancet is forecasting a “jaw-dropping” decline in the planet’s population by 2100, with the number of people in 23 countries expected to drop by half by the end of the century. While fewer humans using up fewer resources might sound like a good thing, the study’s authors warn that a sharp decline in population growth can have serious sociological and economic consequences.
Team Humanity already has 7.8 billion players on its roster—a number that will continue to increase as time goes by—but population growth itself peaked in 1989 when 88 million new people came into the world. That growth rate dipped to 73.9 million in 2003, saw a somewhat smaller peak of 84.8 million in 2013, but has been on the decline since then, with 81.3 million people being born in 2019.
The planet’s population is expected to peak at 9.7 billion inhabitants somewhere around 2064, but will decline to 8.8 billion by 2100. Although some regions are still experiencing population growth, the overall downward trend is being fueled by the increased availability of education for women around the world, allowing them to enter the workforce, along with the improved accessibility of contraception and declining fertility rates, making for fewer deliveries by the stork every year. Already, the number of children the average woman can expect to have over her lifetime has already declined by half over the past 70 years (from 5 in the 1950s to 2.5 in the past decade), and is projected to drop by nearly another 20 percent by the middle of the 21st century.
The study predicts that this population decrease will hit some countries harder than others, with Spain, Portugal, and Thailand expected to have their populations drop by more than half by the end of the century.
“That’s a pretty big thing; most of the world is transitioning into natural population decline,” explains study co-author Christopher Murray, at the University of Washington. “I think it’s incredibly hard to think this through and recognize how big a thing this is; it’s extraordinary, we’ll have to reorganize societies.”
Although a decrease in the world population would appear to be a good thing in regards to the planet’s overburdened resources, this trend has sociological consequences, with fewer young people coming into the world to provide for older generations. This demographic imbalance “will create enormous social change,” according to Murray: “Who pays tax in a massively aged world? Who pays for healthcare for the elderly? Who looks after the elderly? Will people still be able to retire from work?”
New approaches will be needed to both cope with and compensate for this disparity, including more open immigration policies—a measure already being taken by some countries that are experiencing a decline in natural population growth. The robotics industry in Japan, a country where more than one-quarter of the population is over 65, is already developing robots called “carebots” to care for the nation’s elderly, along with powered exoskeletons to aid health care workers in nursing homes.
African nations, at least in the near term, will be the main source of population growth for the world, and won’t experience the declines seen by the rest of the world until after 2100. In fact, the study projects that Nigeria will become the second most populous country on the planet by 2100, with a population of 791 million. Murray says that “We will have many more people of African descent in many more countries as we go through this,” a factor that will force many cultures to address “challenges around racism,” according to Murray, if their cultures and economies are to thrive.