Every two years one million Japanese disappear. China’s population will halve by the end of the century, the median age in Italy has reached 48. All around the world birth rates are crashing – Is humanity dying out?
What is going on and how bad is it? For hundreds of thousands of years the human population barely grew at all, haunted by disease, famine and war until the industrial revolution – exponential progress led to exponential growth, pushing our numbers to 6 billion in the year 1999 and 8 billion just 24 years later. And our numbers will continue to rise for at least another 60 years – but this growth obscures something: People kinda stopped having babies.
For a stable population, every couple needs to have two children on average. If the number is higher it grows, if lower, it shrinks. If it's well below, it shrinks a lot, and quickly: Like in South Korea, one of the hottest exporters of pop culture.
Its fertility rate lay at 0. 8 children per woman in 2022, the lowest in the world. This means 100 South Koreans of childbearing age today will have 40 kids.
Who then will have 16 kids, who then will have 6. If nothing changes then within 100 years there will be 94% fewer young people and South Korea will see a population implosion. That is if things stay the same – we have yet to see if there is a bottom to fertility rates.
Although looking at the bigger picture and absolute numbers, this population will not shrink that much – it simply returns to the level it once was. In 1950 there were 20 million South Koreans, in 2023 there are 52 million. And by 2100 there will be 24 million again.
But the issue is not that there will be fewer South Koreans, the issue is the composition of the population. In 1950 the median age was 18. In 2023 it is 45.
In 2100 it will be 59. A country of seniors. And South Korea is far from alone.
China may be seeing the steepest population reversal in history, unstoppable at this point. Rapid industrialization, urbanisation and rising incomes meant that the Chinese started to prefer smaller families. That, plus the introduction of the One Child Policy, which aimed to slow population growth, means that China has had a low fertility rate for decades.
With a fertility rate of 1. 16 births per woman, within four generations 100 young Chinese will turn into 20. China's fertility rates are now one of the lowest in East Asia, lower than even Japan's.
In comparison Europe’s depopulation is much slower despite low fertility, since unlike Asia most states have had a steady flow of immigrants. The impact is complex, as a good chunk of immigrants come from other low fertility rate areas, the number of immigrant women who do have a lot of children is not yet high enough to make a big dent and fertility rates of immigrants tend to adjust to the native population within 2-3 generations. In Eastern Europe, the decline has sped up even more because many young people have emigrated to stronger economies, like Germany – whose median age is one of the highest in the world at 46.
Latin America fell below replacement in 2015. In the US, immigration is the only thing keeping the population growing substantially. There are still places where fertility rates have not fallen below replacement yet: In much of the Middle East, North and Sub Saharan Africa fertility is still high, which creates the same concerns about overpopulation as when Asia grew very quickly in the 1950s, but that turned out to be unfounded.
But recently the UN has reduced its forecast for Africa’s population drastically. For Nigeria estimates were lowered from 733 million to 546 million by 2100. Similar trends are being noted across the continent.
As Africa develops, fertility rates are shrinking much faster than anticipated. It is becoming more likely that East Asia’s story will repeat itself – by the end of the century most places in Africa may be below replacement too. So declining fertility rates and ageing populations have become a general trend, all over the world.
Why is all of this a big deal? Demographics & Poverty For a functioning society you need enough people in the prime of their lives. Young and middle aged people do most of the work.
In any economic system, working age people create a society’s wealth. In retirement you stop contributing as much to the economy. But the majority of healthcare costs are generated by seniors.
The way the world worked in the past was that a lot of younger people took care of a few older people. Imagine a society where most people are older than 60. The financial burden for the young will be immense, unsustainable even for the richest countries.
Even in the best case this will mean people having to work way longer, exploding health care costs and poverty, while states with shrinking income struggle to keep up with rising costs. Technology might soften the blow, but can’t compensate entirely. We can see this happening already – 11 out of 31 provinces in China are running deficits for their pension funds.
They got old before they got rich and now they can’t really catch up anymore. China’s working age population is predicted to fall by 20%, or 200 million people by 2050 – as much as today’s entire working age population of the US. Infrastructure collapse is an almost universal constant of population decline.
Because infrastructure works at scale and doesn’t get cheaper to operate if it is used by fewer people. If a population declines, be it because of urbanisation or the loss of industry and employment – once people and their income disappear, the resources necessary to sustain infrastructure disappear too. You can see it in many depopulated towns and cities in East Germany that suffered sharp population decline after German reunification.
Or look at Japan. You can tour the countryside to see dying towns. Wait – if there are fewer people, won’t life get cheaper and better and there’ll be more resources to go around?
Well no – population decline doesn't lead to prosperity. It’s people’s ideas and work that create our prosperity, not the mere availability of resources. Another danger for ageing societies is that elected governments could decide to mostly represent the interests and fears of their elderly populations – potentially leading to short term thinking and a preference for conserving wealth over innovation.
That's not a society that can handle issues like climate change, which need massive investment and fresh ideas – something the world is already having a hard time with. Many people think that having fewer humans on earth is actually a good thing because our societies are too unsustainable, we are using up too many resources and because of climate change. The problem is, that even if you want fewer humans, this process is very likely too slow to have a positive impact on the environment – the world population is going to grow for at least 60 more years before it may shrink again – by then we have to solve climate change.
Likewise, any other upsides a lower population might have will most likely not materialise themselves this century. So Just Like Import People? The easiest solution seems to be immigration, but the fertility of immigrants adjusts to local levels within three generations.
So you need a constant influx of new migrants – which is not sustainable long term as birth rates are dropping everywhere. The only way would be to keep poor countries poor, so that the young and motivated migrate to developed countries, looking for opportunity and a better life. Kind of an immoral thing to wish for.
By the end of the century Africa will have the highest number of young people in the world and so African migrants might become the world's most sought after immigrants, with elderly nations fighting hard for every person willing to make the move. Immigration also can create societal or cultural tensions, which is a universal phenomenon in all cultures – especially when cultures with very different sets of values meet – often leading to a backlash that slows immigration down again. It’s easy to be frustrated at this, but ignoring this will only divide societies, empower demagogues and increase xenophobia.
Economically, immigration is largely beneficial for societies, even if this seems counterintuitive to many people. Especially countries like the US, an immigrant nation built on the idea of personal freedom and opportunity through hard work, will benefit the most. Countries like this will have a clear advantage this century, especially if they can attract the world’s brightest and most ambitious.
Conclusion & Our Opinion This topic is way too big, affects societies as diverse as literally all of humanity. So please take this part with a gigantic grain of salt, obviously we are looking at this from our central European perspective. One way to look at falling birthrates is as a side effect of the world being less bad than it was.
Especially women are freer, more educated and wealthier than in the past. But it turns out that if societies are better off, individuals often decide to have fewer kids. Interestingly, there is a gap between how many kids people want and how many they are having: The mean number of kids women in Europe want is around 2.
3, much more than they are actually having. While we gained a lot of freedoms in the last century, across continents and economic systems, that came at a cost: The tight knit communities and family structures that were part of our nature, where kids could be brought up by a village. Today young parents have to deal with different challenges and societal expectations.
Women are kind of ground down between the wish and expectation to have a family and a career, being pressured to do both but not compromise either. Men are sharing parental duties more equally than they used to, but are often still expected to be the provider. And it is sadly true that usually, at least one parent's career is held back.
In many developed countries the gender pay gap is chiefly a pay gap between mothers and everyone else. But it is not just outside pressure: Our culture of individualism probably plays a role too. We have only one life to explore, be free, travel, have fun, accomplish something and try to be happy.
So people commit to partners later in life and often decide against big families or any at all. And that’s fair, nobody owes their country babies. So far no country has successfully managed to increase birth rates significantly, so as of now we don’t really know what works.
But here are a few options to at least make the lives of parents much easier: free and abundant access to childcare, financial benefits for parents, more and cheaper housing. Parenthood has to stop being a career obstacle. And our culture needs to become more positive towards families.
And that is something we can all work on. The next time you sit next to a crying baby – don’t be a jerk about it. Kids are hard.
In the end, humanity will not die out because we're having fewer babies. The age and composition of our societies changes quickly and we need to deal with that sooner rather than later. But in the end, of all the incredibly hard challenges we faced before, why would this be the one we can’t solve?
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