Why is this happening? Why is the birth rate falling?

First, I want to step back and say, well, birth rates are collapsing.

Some people don't like that word collapsing.

I've been criticized for it.

I probably tend not to use it as much right now because it implies that something's wrong.

And others would prefer to call it a phenomenon.

Okay, interesting.

As a cultural shift indeed, yeah.

planet at some future time.

At some future time.

And to me, the first thing, my reaction, strong reaction, isn't there another way, if that's right? And then you look at data as a report in Nature last year on the overall footprint by age group.

Quite a number of scientists put their name to it, and it's very clearly that 8% of our footprint occurs when we're aged under 30. then it rises quite significantly between 30 and around 65, I believe, and then it falls off sharply.

Well, that means that if the world's births were to magically, well, it wouldn't be magic, drop by, say, half, I love taking extreme situations, so let's imagine that from tomorrow, only half of the births happen for some crazy reason, that 8% of total emissions or footprint would go down to 4% in 30 years' time.

This is going to have almost no impact for decades at a time when I think we have to find other solutions as much as they're needed to solve problems that are out there.

So the idea that we're going to inflict this pain, deep personal suffering, pain in people, and perhaps be pleased about it, as I know some people are, I think is terribly sad.

tens and tens of thousands of decaying

Those are the places where the death toll will become apocalyptic.

Well, I agree places like Thailand are in for an extraordinary level of old age, loneliness and challenges.

India, my gosh, my worry about India population right now is its aging population two, three decades from now.

No one's thinking about that.

That's a humanitarian crisis.

It's a ticking time bomb.

In terms of happiness, I think one of the things we have to isolate out here is the 10% of people who don't want children.

Is this still correct, this data?

Um, do you think political philosophies have influenced these numbers, Stephen, such as feminism and the idea that actually for a woman, a career might be more valuable and important than having a family?

Um, it's, it's absolutely not as simple as that a-a-at all.

One of the most remarkable things for me is when you look at data, uh, again, I, you know, I live in Japan, I study it, or 24 countries intimately in terms of long-term birth rate trends.

When you go through shifts in social culture and education levels for women, all of these things, mothers, again, to make the same point, I think it's worth doing, mothers tend to have exactly the same number of children through all of those things.

What simply happens is more and more people perhaps choose not to have children, though the data shows that that's a really very small number overall.

It's people missing out.

So you could say, yes, that, uh, you know, s-social, political changes have influenced this.

The flip side of that is that are they not facing the worst demographic time bomb of all because of that approach?

And you've been working on this for two decades, flying around the world.

Um, it's just over one decade.

It feels like two.

You know, I come from a very different perspective.

I came out of the commercial world, uh, where I ran a data science company doing advanced data modeling for 20 years.

And I, I could've and maybe should've continued in that line, but once I saw in January 2016 that the birth rate issue wasn't just limited, as I thought at that time, to Japan and Italy, that effectively it was spreading globally and had been spreading for 50 years, and I didn't know about it, and for sure I was bringing up my kids at that time, as teenagers as they were, for a world where birth rate decline was not going to be a factor for their, the entirety of their future.

I got scared that w- why do we not know about this? And then going to research to find out, well, what's a common factor? Because we can't have independent factors alone explaining why this happened in Italy and Japan and Germany and Spain and Austria, et cetera, at effectively the same time.

Stephen, give me a couple of information shocks.

Why do birth rates matter? Like, why is decline a problem at all? Why should people care?

I would say that even if you don't care about birth rates, you should at least understand that it's going to impact almost everything in your life, young and old.

In fact, young more than old.

By definition, the young have more years to live through and they've gotta live through the youth and all the way through old age.

And the only thing I can possibly think of that will not be greatly affected by birth rate decline is parks.

I guess parks will continue to be there.

Maybe they'll become more wilded in some way.

Yeah.

(laughs)

...

even doubt myself that this would be a curve that starts smooth and shows all this bumpiness as people, through autonomy, decide whether to have a child at 35 or 39.

Um, but what I saw was a smooth curve in 1,539 datasets.

Very slight perturbations, very slight for periods of time.I stared at that screen.

I, I wrote an email to myself that night, and I, I don't think I've ever done that before, ever will, 'cause I wanted to remember the moment.

Uh, so this is a symmetrical curve, centered around an age, and today let's say it's around 30.

Mm-hmm.