This is a linkpost for https://ourworldindata.org/explorers/population-and-demography
The UN releases an update of its World Population Prospects every two years. Its latest release was due in 2021 but was delayed as a result of the pandemic. But today, the long-awaited dataset has been released.
With early access to this new UN data, we have published a new Population and Demography Data Explorer on Our World in Data, where you can explore this full dataset in detail.
To complement this data explorer, we've also published a post on the Five key findings from the 2022 UN Population Prospects.
All metrics are available:
- For every country in the world, continent, and World Bank income group
- With projection scenarios up to the year 2100
- Broken down by sex and age group
Here's the full list of metrics:
- Age structure
- Population density
- Births (absolute & rate)
- Deaths (absolute & rate / all ages, child, infant)
- Life expectancy
- Sex ratio
- Dependency ratio
- Median age
Thanks, I think it's great to make this data available and to discuss it.
FWIW, while I haven't looked at any updates the UN may have made for this iteration, when briefly comparing the previous UN projections with those by Vollset et al. (2020), available online here, I came away being more convinced by the latter. (I think I first heard about them from Leopold Aschenbrenner.) They tend to predict more rapidly falling fertility rates, with world population peaking well before the end of the century and then declining.
The key difference in methods is that Vollset et al. model fertility as partly depending on educational attainment and access to contraceptives. By contrast, I believe the UN (at least in the previous iteration) primarily did a brute extrapolation of fertility trends.
Assume we believe the causal claim that increased educational attainment and access to contraceptives causes lower fertility. Then modeling these two causes explicitly will beat a brute extrapolation of fertility if there are countries which:
And I think this happens to apply to quite a few countries.
this time, the WPP does show a population decline before the end of the century, though they still have a later and higher peak than Vollset et al.
prior to the update, the UN projections were clearly worse than the Vollset ones, now that their projections are closer together, I'm less confident which one is likely closer to the truth. but lean towards Vollset still being better and the UN not having revised down enough yet.
also, fun observation: two of the eight countries contributing most to growth in the next three decades already have shrinking birth cohort sizes, because even though cohorts are getting smaller than previous years, they're still much larger than the elderly population which has the highest mortality rates. (India and the Philippines, though note that there is a really wide discrepancy between Philippines estimates of births and WPP estimates of births, which is wider than what the birth registration gap is purported to be)
I saw these articles [1-2]/tweet  on a researcher claiming that China's population is significantly lower than what's stated in the official China/UN sources, so much as he estimates 1.28 instead of 1.41 billion.
I am Curious if anyone knows whether there is some truth to that claim and whether the UN takes the official national data at face value or do independent estimates of some kind?
 https://www.project-syndicate.org/commentary/china-2020-census-inflates-population-figures-downplays-demographic-challenge-by-yi-fuxian-2021-08 [Paywall]
I suspect there's a good chance that populations in Western nations could be significantly higher than predicted according to your link. The reason for this is that we should expect natural selection to select for whatever traits maximize fertility in the modern environment, such as higher religiosity. This will likely lead to fertility rates rebounding in the next several generations. The sorts of people who aren't reproducing in the modern environment are being weeded out of the gene pool, and we are likely undergoing selection pressure for "breeders" with a strong instinctive desire to have as many biological children as possible. Certain religious groups, like the Old Order Amish, Hutterites, and Haredim are also growing exponentially, and will likely be demographically dominant in the future.
I think this is a relevant consideration, but murkier than it appears at first glance.