John Burn-Murdoch

And there's fairly strong consensus on what was happening there.

So...

You had child mortality getting much lower.

So in effect, you didn't need to have as many kids to end up with as many children.

You had this shift from farming to manufacturing and services, which changed the number of kids you needed to sort of support the family business, as it were.

That also came with urbanization, which generally meant fewer kids.

And you had increasing female education, all these very slow moving trends.

We have good evidence that that was what was explaining the shift from, say, four kids to three kids to two kids per woman.

Then, late 20th century and the start of this century, things were fairly stable.

They're pretty stable in high income countries, but they even started to stabilize in middle income countries, places like Latin America.

But then suddenly, around 2010, in some places slightly before, some places closer to sort of 2015, you get a new decline.

And here we're going down from about two or sort of 1.8 kids per woman down to the sort of 1.5, 1.4, or even as some of your listeners I'm sure will be aware in places like Korea, down to an average of less than one.

Yeah, the more to go around point is a nice one because the evidence is that it's almost the opposite.

Now, obviously, in some senses, there's more to go around.

If we say that there are a fixed amount of natural resources on the planet, then fewer people competing for those resources, that's reducing pressure.

But in terms of the things to go around that we're mainly concerned about in our daily lives, which is the things produced in an economy, those things are produced by workers.

And if you have fewer young people, that means with each generation, you have fewer workers and the people producing the stuff are a smaller and smaller and smaller share of the population.

So Japan is a fascinating example of this, right?

So people have looked at Japan for the last 30 years and said, you know, what happened to those guys?

They used to be on top of the world.