[vmurthy]

For me this stood out: "The reference projections for the five largest countries in 2100 were India (1·09 billion [0·72–1·71], Nigeria (791 million [594–1056]), China (732 million [456–1499]), the USA (336 million [248–456]), and Pakistan (248 million [151–427])."

The big surprise being China,of-course. A drastic decrease projected in the coming 80 years.Should have policy consequences as well, I would think.

[Someone]

China’s predicted population decrease is a logical consequence of its one child policy (https://en.wikipedia.org/wiki/One-child_policy)

If you compare https://www.populationpyramid.net/china/1980/ with https://www.populationpyramid.net/china/2020/, you see how drastic its effect on China’s population pyramid was. Drastically fewer kids means fewer parents 20-30 years later.

(There also is a bit of an effect of richer people having fewer children, but for China, that effect is relatively small)

[snovv_crash]

Added to this, their economy has boomed due to not having to invest in future generations. At some point of course these chickens will come home to roost when the current population hump gets to an age where they retire, but for a good 20 years it can be a massive economic boon.

[ilstormcloud]

>Added to this, their economy has boomed due to not having to invest in future generations.

Can you clarify on what you mean by that please? Are you referring to pollution an environmental degradation?

[DrFalkyn]

Adults can work more and be more productive if they don’t have to take care of children

[7374ureuruu]

This is a non-issue for most asian countries. Grandparents and women who couldn't keep up with men in professional settings become caretakers. China's biggest issue is its population bomb not a lack of people to watch the kids.

[snovv_crash]

It isn't just at a young age that kids need watching, and time isn't the only resource invested in children.

Think of the percentage of any modernizing economy that goes into things like food and clothing for children, education and educational materials, transport, energy consumption. The reduced output of parents who are tired from looking after or arguing with children. And this is for something that won't start putting value back into the economy for a good 18 years from initial investment.

Skip this, and instead of food and clothes for children adults can spend on housing, transport, take risks with starting businesses without the chance of hungry dependants, etc

[vmurthy]

By productive if you mean only time-wise, don't forget that single kid families can increase consumption of goods with the saved Yuan leading to higher GDP as well.

[shalmanese]

Population Pyramid estimates the 2100 population of China to be 1.06B which is 45% higher than the 732M figure estimated by Lancet.

1B feels like a lot more realistic estimate than 750M.

[vmurthy]

The most interesting thing for me in this report coming out is that societies/governments taking note of this might incentivise outcomes. E.g., if China thinks that 750M is too low keeping its longer term interests, it might tweak the 1-child policy or encourage immigration etc by 2050.

[robbiep]

The lancet error bars are 456 - 1499.

[GlennS]

Really interesting website, thanks for linking that.

[downvoteme1]

Isn’t this too much of variability. For example it projects India’s population range from 0.72B to 1.71B . That is like either being number one by a wide margin or dropping to 10th spot or lower.