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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