I have a suspicion that one of the reasons is that fertility is calculated in a wrong way.
We can't observe total fertility - we only observe the number of children which was born in a given year. To get fertility we need some assumptions about future average female fertility timing (eg that if they will have children, it will happen between 18 and 40 years old).
However, many females choose to have children older in life, closer to 40 and they have technical means to do it like in vitro fertilizations etc.
Except that the thing which is called the TFR is calculated as the fivefold sum of births per woman-cohort per year, where the cohorts are ages 15-19, ..., 45-49 and every summand is observed across the years. Were, say, South Korean population to stabilize without raising the thing called the TFR, it would mean that women give birth in a way unreflected by the statistics, i.e. after reaching 50 years. But there is unlikely to be a boom of that late births.
There are two sides of developments in fertility.
Today I’m going to focus on news about what is happening and why, and next time I’ll ask what we’ve learned since last check-in about we could perhaps do about it.
One could consider all this a supplement to my sequence on The Revolution of Rising Expectations, and The Revolution of Rising Requirements. That’s the central dynamic.
Household Composition
What is happening? A chart worth looking at every so often.
Timing
This is United States data:
The replies include a bunch of other graphs that also go in bad directions starting in 1971-73.
Developmental Idealism
Lyman Stone, in his first Substack post, lays the blame for fertility drops in non-Western countries primarily on drops in desire for children, via individuals choosing Developmental Idealism.
The central point of idea #1 is you have to look at changes over time, as in:
The overall central thesis:
So in this model, the question becomes why are desired family sizes falling?
Lyman thinks this mostly comes down to comparisons with others (he explicitly doesn’t want to use the word ‘status’ here).
And his thesis is essentially that people around the world saw European wealth, found themselves ‘at the bottom’ of a brand-new social scale, and were told to fix this they had to Westernize, and Western culture causes the fertility decline.
This doesn’t explain where the Western desire for smaller families came from.
I also don’t think that this is why Western culture was adapted. I think Western culture is more attractive to people in various ways – it largely wins in the ‘marketplace of ideas’ when the decisions are up to individuals. Which I think is largely the level at which the decisions are made.
Pessimism
People’s severe pessimism, and inability to understand how good we have it, is making all these issues a lot worse.
Are there big downsides and serious issues? Oh, definitely, atomization and lack of child freedoms and forms of affordability are big problems, and AI is a big risk.
Baby Boom
Saloni Dattani and Lucas Rodes-Guirao offer us a fun set of charts about the baby boom, but they don’t offer an explanation for how or why that happened, as Derek Thompson points out none of the standard explanations fully line up with the data. A lot of people seem to grasp at various straws in the comments.
Handy and Shester do offer an explanation for a lot of it, pointing to decline in maternal mortality, saying this explained the majority of increases in fertility. That is certainly an easy story to tell. Having a child is super scary, so if you make it less scary and reduce the health risks you should get a lot more willingness to have more kids.
Tyler Cowen sees this as a negative for a future baby boom, since maternal mortality is now low enough that you can’t pull this trick again. The opposite perspective is that until the Baby Boom we had this force pushing hard against having kids and people had tons of kids anyway, whereas now it is greatly reduced, so if we solve our other problems we would be in a great spot.
Paperwork
The paperwork issue is highly linked to the safety obsession issues, but also takes on a logic all its own.
As with car seat requirements, the obvious response is ‘that’s silly, people wouldn’t not have kids because of that’ but actually no, this stuff is a nightmare, it’s a big cost and stress on your life, it adds up and people absolutely notice. AI being able to handle most of this can’t come soon enough.
Car Seats As Contraception
Back in 2022 I wrote an extended analysis on car seats as contraception. Prospective parents faced with having to change cars, and having to deal with the car seats, choose to have fewer children.
People think you can only fit two car seats in most cars. This drives behaviors remarkably strongly, resulting in substantial reductions in birth rates. No, really.
The obvious solution is that the extent of the car seat requirements are mostly patently absurd, and can be heavily reduced with almost no downsides.
It turns out there are also ways to put in three car seats, in many cases, using currently available seats, with a little work. That setup is still annoying as hell, but you can do it.
The improved practical solution is there is a European car seat design that takes this to four car seats across a compact. It can be done. They have the technology.
In an even stupider explanation than usual, the problem is that our crash test fixtures that we use cannot physically include a load leg, so we cannot test the four car seat setup formally, so we cannot formally verify that they comply with safety regulations.
You would also have to spread the word so people know about this option.
You Can’t Afford It
Of course you are richer than we used to be, but not measured in the cost to adhere to minimal child raising standards, especially housing and supervision standards.
Yes The Problem Is Often Money
Here is the latest popping up on my timeline of ‘how can anyone have kids anymore you need a spare $300k and obviously no one has that.’
That is indeed about what it costs to raise a child. If you shrink that number dramatically, the result would be very different, at least in America.
America has the unique advantage that we want to have children, and like this man we are big mad that we feel unable to have them, usually because of things fungible with money. So we should obviously help people pay for this public good.
Housework
There is the housing theory of everything. Then there’s the housework theory of everything?
Even the green bars are 1.7-1.8. That’s still below 2.1, even with a somewhat cherry-picked graph.
Also this is rather obviously not the right explanatory variable.
Why should we care about how many hours of housework a woman does more than the man, rather than the number of hours the woman does housework at all?
The suggestion from Goldin is more subsidized child care, but that has a long track record of not actually impacting fertility.
The actual underlying thing is, presumably, how hard it is on the woman to have children, in terms of both absolute cost – can you do it at all – and marginal cost versus not doing it. The various types of costs are, again presumably, mostly fungible.
The idea that ‘50-50’ is a magic thing that makes the work go away, or that it seeming fair would take away the barrier, is silly. The problem identified here is too much work, too many costs, that fall on the woman in particular, and also the household in general.
One can solve that with money, but the way to do it is simply to decrease the necessary amount of work. There used to be tons of housework because it was physically necessary, we did not have washers and dryers and dishwashers and so on. Whereas today, this is about unreasonable standards, and a lot of those standards are demands for child supervision and ‘safety’ or ‘enrichment’ that simply never happened in the past.
Greedy Careers
If market labor has increasing returns to scale, then taking time off for a child is going to be expensive in terms of lifetime earnings and level of professional advancement. Ruxandra’s full article is here, I quote mostly from her thread.
A lot of the problem is our inability to realistically talk and think about the problem. There’s no solution that avoids trading off at least one sacred value.
The Appeal of Child-Free
It’s definitely super annoying that when you have kids you have to earn your quiet. This both means that you properly appreciate these things, and also that you understand that they’re not that important.
Motivation
I too do not see this as the message to be sending:
Becoming a parent also makes it extremely logistically tricky to go to the movies, or to go out to dinner, especially together. Beyond that, yes, obviously extremely tone deaf.
The basic principle here is correct, I think.
Which is, first, that most people have substantial slack in their living expenses, and that in today’s consumer society your expenses will expand to fill the funds available but you’d probably be fine spending a lot less. Digital entertainment in particular can go down to approximately free if you have the internet, and you’ll still be miles ahead of what was available a few years ago at any price.
And second, that if you actually do have to make real sacrifices here, it is worth doing that, and historically this was the norm. Most families historically really did struggle with material needs and make what today would seem like unthinkable tradeoffs.
Also third, although she’s not saying it here, that not being able to afford it now does not mean you can’t figure it out as you go.
Another form of motivation:
Another key form of motivation is, what are you getting in return for having kids? In particular, what will your kids do for you? How much will they be what you want them to be? Will they share your values?
The post mostly focuses on the various ways Indian parents shape the experiences of their children including getting transfers of resources back from them but mostly about upholding cultural and religious traditions, and how much modernity is fraying at that. For many, that takes away a strong reason to have kids.
Grandparents
The New York Times put out an important short article that made people take notice, The Unspoken Grief of Never Becoming a Grandparent.
I have little doubt that those considering having kids are not properly taking into account the grandparent effect, either for their parents or in the future for themselves.
Throughout, the frame is ‘of course my children should be able to make their own choices about whether to have kids,’ and yes no one is arguing otherwise, but this risks quickly bleeding into the frame of ‘no one else’s preferences should factor into this decision,’ which is madness.
It also frames the tragedy purely in experiential terms, of missing out on the joy and feeling without purpose. It also means your line dies out, which is also rather important, but we’ve decided as a society you are not allowed to care about that out loud.
The flip side is that parents, who are prospective grandparents, seem unwilling to push for this. Especially tragic is when they hoard their wealth, leaving their kids without the financial means to have kids. There is an obviously great trade for everyone – you support them financially so they can have the kids they would otherwise want – but everyone is too proud or can’t admit what they want or wants them to ‘make it on their own’ or other such nonsense.
Audrey Pollnow has extensive thoughts.
I appreciated this part of her framing: Having kids is now ‘opt-in,’ which is great, except for two problems:
I do not agree with her conclusion that therefore contraception, which enables us to go to ‘opt-in,’ is bad actually. That does not seem like the way to fix this problem.
Expectations of Impossibility
On top of how impossible we’ve made raising kids, and then we’ve given people the impression it’s even more impossible than that.
Potential parents are also often making the decision with keen understanding of the downsides but not the upsides. We have no hesitations talking about the downsides, but we do hesitate on the upsides, and we especially hesitate to point out the negative consequences of not having kids. Plus the downsides of having kids are far more legible than the benefits of kids or of the downsides of not having kids.
Isolation
The shading here makes it look a lot more dire than it is, but yes a lack of other kids makes it tougher to have or decide to have your own.
The first best solution is different from what an individual can do on the margin.
I see the problem of childcare as not ‘the parents are spending too little time with the kids’ but rather ‘we require insane levels of childcare from parents’ so the rational response is to outsource a bunch of that if you can do it. The ideal solution would be to push back on requiring that level of childcare at all, and returning to past rules.
Decoupling
Alice Evans notes that unlike previous fertility declines, in the United States the recent decline is almost entirely due to there being fewer couples, while children per couple isn not changed.
This is at least a little misleading, since desire to have children is a major cause of coupling, and marginal couples should on average be having fewer children. But I do accept the premise to at least a substantial degree.
Also noteworthy is having less education means a bigger decline:
This is happening worldwide, and Alice claims it corresponds with the rise in smartphones. For America I don’t see the timing working out there? Seems like the declines start too early.
Then she turns to why coupling is plummeting in the Middle East and North Africa.
The first explanation is that wives are treated rather horribly by their in-laws and new family, which I can totally see being a huge impact but also isn’t at all new? And it’s weird, because you wouldn’t think a cultural norm that is this bad for your child’s or family’s fertility would survive for long, especially now with internet connectivity making everyone aware how crazy it all is, and yet.
It’s so weird, in the age of AI, to see claims like “The decline of coupling and fertility is the greatest challenge of the 21st century.”
South Korea
This framing hit home for a lot of people in a way previous ones didn’t.
Robots, AI and automation might mitigate the effects along the way and prevent total societal collapse for a while, but there would soon be no one left to constitute the society. It would cease to exist.
It’s so tragic that a lot of this is a perception problem, where parents think that children who can’t compete for positional educational goods are better off not existing.
The article goes on and things only get worse. Workplace culture is supremely sexist. There’s a 1.15:1 male:female ratio due to sex selection. Gender relations have completely fallen apart.
The good news is that marginal help helped. The bad news is, you need More Dakka.
If you ask for a $270k expense, and offer $22k in subsidy, that helps, but not much.
The result here is actually pretty disappointing, and implies a cost much larger than that in America. The difference is that in America we want to have more kids and can’t afford them, whereas in South Korea they mostly don’t want more kids and also can’t afford them. That makes it a lot harder to make progress purely with money.
It’s plausible that this would improve with scale. If the subsidy was $30k initially and then $15k per year for 18 years, so you can actually pay all the expenses (although not the lost time), that completely changes the game and likely causes massive cultural shifts. The danger would be if those funds were then captured by positional competition, especially private tuition and tutoring, so you’d need to also crack down on that in this cultural context. My prediction is if you did both of those it would basically work, but that something like that is what it would take.
2024 was the first year since 2015 that total births increased in South Korea, by 3.1%, which of course is not anything remotely like enough.
Robin Hanson points us to this article called The End of Children, mostly highlighting the horror show that is South Korea when it comes to raising children.
Timothy Taylor takes a shot at looking for why South Korea’s fertility is so low, nothing I haven’t covered before. I’m increasingly leading to ‘generalized dystopia’ as the most important reason, with the mismatch of misogyny against changing expectations plus the tutoring costs, general indebtedness and work demands being the concrete items.
World
Various Places in Trouble
China
China did have a widespread improvement from 2023 to 2024, but only to 1.1, and this was plausibly because it was the Year of the Dragon. In 2025 things seem back to 2023 levels, so it doesn’t look like they’ve turned a corner.
China’s marriage rate is collapsing, now less than half of its peak in 2013, and down 20% in only one year.
As a reminder, these are the demographics, they do not look good at all, watch the whole chart slowly creep older and the bottom crisis zone that started in 2020 expand.
AI will presumably upend the game board one way or another, but the most absurd part is always the projection that things will stabilize, as in:
The article has that graph be ‘if China’s fertility rate doesn’t bounce back.’ Whereas actually the chart here for 2050 is rather optimistic under ‘economic normal’ conditions.
Their overall map looks like this:
They are at least trying something in the form of… changes to divorce?
One change in particular seems helpful, which is that if a parent gifts the couple real property, it stays with their side of the family in a divorce. I like this change because it makes it much more attractive to give the new couple a place to live, especially one big enough for a family. That’s known to have a big fertility impact.
What impact will that have on fertility?
Russia
Russia’s birth rate continues to rapidly drop to its lowest point in 200 years, with its population actively declining. Having started a protracted war is not helping matters.
Europe
America
This is what a relatively healthy demographic graph looks like in 2025.
We still primarily need office to residential because of the three rules of real estate, which are location, location, location. You can put the retirement communities in rural areas and find places you’re still allowed to build.
New Mexico to offer free child care regardless of income. As usual, I like the subsidy but I hate the economic distortion of paying for daycare without paying for those who hire a nanny or stay home to watch the kids, and it also likely will drive up the real cost of child care. It would be much better to offer this money as an expanded child tax credit and let families decide how to spend that, including the option to only have one income.
Kazakhstan
Kazakhstan remains the existence proof that fertility can recover, with economic recovery and growth boosting seemingly rather than hurting fertility as they recovered from the economic woes they experienced in the 1990s.
Israel
More Births looks into how Israeli fertility remains so high.
Israel has high levels of education. It has high housing costs. It has existential threats from outside, but so do Ukraine and Azerbaijan. Israeli levels of religiosity are unremarkable, only 27% attend a service weekly and secular Jewish fertility is around replacement. Social services are generous but not unusually so.
The conclusion is, a lot of things matter, but what matters most is that Israel has strong pronatal beliefs. As in, they rushed dead men from the October 7 attacks to the hospital, so they could do sperm extractions and allow them to have kids despite being dead.
Consequences
Fix your fertility rate, seek abundance beyond measure, or lose your civilization.
Your call.
Unfounded Optimism
Why do official baseline scenarios consistently project recovering fertility rates?
Compare the lines. This is not how a reasonable person would update based on what has happened since the year 2000. It could go that way if we play our cards right, but it sure as hell is not a baseline scenario and we are not currently playing any cards.
History
For most of history the rich had more children that survived to adulthood than the poor. Then that reversed, and this is aying that in Britain this happened big time in the late 1800s.
Claim that only 1% or less of children are genetically unrelated to their presumed fathers, very different from the opt-repeated figure of 10%. That’s a very different number, especially since a large fraction of the 1% are fully aware of the situation.
Implications
The Social Security administration and UN continue to predict mysterious recoveries in birth rates, resulting in projections that make no sense. There is no reason to assume a recovery, and you definitely shouldn’t be counting on one.
I do think such projections are ‘likely to work out’ in terms of the fiscal implications due to AI, or be rendered irrelevant by it in various ways, but that is a coincidence.
Fertility going forward (in ‘economic normal’ worlds not transformed by AI) will have highly minimal impact on climate change, due to the timing involved, with less than a tenth of a degree difference by 2200 between very different scenarios, and it is highly plausible that the drop in innovation flips the sign of the impact. It is a silly thing to project but it is important to diffuse incorrect arguments.