- A. There will be more children (age below 15)
- B. There will be more adults (age 15 to 74)
- C. There will be more very old people (age 75 and older)
According to the UN Population Prospects dataset, by 2100 the world’s population will have risen by a little over 3.6 billion compared to 2017. The adult population of the world will have risen by 2.5 billion—that’s 68.5% of the anticipated population growth.
Despite all the media attention on the “ageing population”, very old people will account for less than ⅓ (31%) of the projected population increase. And the UN estimates that children under the age of 15 will account for less than 0.5% of population increase by 2100—an increase of just 17.5 million children.
You can view the full dataset (compiled by Gapminder) here.
The ignorance we found
Yet again our respondents failed to beat the chimps! A terrible 26% of our respondents chose the right answer.
This time it was our US respondents who scored highest, with 36% correct answers, while Japan brought up the rear with just 10% selecting the right answer.
Why do people pick the wrong answer?
In many ways, the ignorance around this question isn’t very surprising. In nearly every rich country, the “ageing population” problem has received a huge amount of attention from the media, politicians, and educators.
Unfortunately, most of this attention hasn’t done a good job of explaining how ageing populations actually work. This leads many people to assume the average age of the world’s population will just keep going up in a straight line… which of course it won’t.
Right now, many countries do indeed have ageing populations, which are caused primarily by three things:
- Increased life expectancy
- Fewer babies being born per woman
- The well-publicized “baby boom” of the mid-twentieth century
Yes, you read that last item correctly. Because so many people were born during a relatively short period of time—with fertility rates dropping off afterwards—that means there will also be a time where there is a particularly large cohort of old people. It’s the same group of people, just grown up. But fast-forward a generation or so, and—assuming birth rates remain fairly stable—a lot of this problem will be smoothed out.
But none of this gets a lot of attention in the media, so most people just aren’t aware of it. Add this to the misconception about birth rates causing rising populations, and you’re left with a lot of people who have very little idea how their world will evolve over the next eight decades.