Cities exist because they offer economic and social benefits. People generally come to cities to make money, find a partner, and interact with other humans. Occasionally, we underestimate this desire to cluster — which was the case during our recent pandemic. But the reality is that this is a human tendency that has existed for thousands of years and that also happens to be accelerating.

I mean, as recent as 1980, only about 40% of the world's population was living in an urban area. Today, this figure is closer to 60%, and by 2080, it is predicted that up to 90% of the people on this planet will live in an urban center.

This will take the number of megacities with over 10 million people from 3 (in 1980) to nearly 100 in 2080 (according to projections from UN-Habitat). But here's the thing: cities help people become wealthier, but once people become wealthier, they tend to have far fewer children. This inverse correlation is well established. So intuitively, there should be limits to the growth we are seeing.

Here's an interesting article from CityLab by Greg Clark, Borane Gille and Jennifer Dolynchuk that pegs this peak somewhere around 2080. We will still remain extremely urban, but overall our population will start to decline. And for some cities, like Tokyo, this decline has already started.

Charts via CityLab