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

One of the many differences between Canada and the US is that our roads are less deadly. A new study by the US Insurance Institute of Highway Safety and the Canadian Traffic Injury Research Foundation found that between 2010 and 2020, total road deaths in the US rose 18%, while in Canada they declined 22%.

This "crash gap" also widens when you look at deaths per vehicle mile driven (as opposed to per capita), which should, in theory, normalize the fact that Americans tend to drive more on average than Canadians. So why might this be? Both countries are broadly car-oriented, at least compared to the rest of the world.

The study presents a number of possible explanations: Canada has stricter drunk driving laws, Canada uses more traffic cameras, Canadians are relatively poorer and therefore drive less, Canada has higher gas taxes (which discourage driving), and the list goes.

But my unproven theory is that a lot of this gap can be explained by differences in the built environment. Solutions like traffic cameras are, to give just one example, what you do when you've failed to design the road you actually want. They're patches, not fixes.

The root problem is the design of the road itself, which is why New Yorkers are only about a third as likely to die from a transportation-related accident compared to the average American. Why? Because it's an urban place designed around non-car mobility.

Conversely, this is also why the top 20 most deadly metro areas in the US for pedestrians are in the south, as opposed to in older northern cities. And it's because these tend to be newer car-oriented metros.

So when it comes to Canada vs. the US, I suspect that much of the gap can be explained by differences in the physical environment and higher transit usage north of the border. It probably also explains why Canada is safer than the US, but not safer than Europe when it comes to transportation-related fatalities. We're simply not urban enough.

The simple takeaway is that the more you optimize your environment for cars, the more dangerous you make it for humans.

That said, this is likely to change with the continued adoption of autonomous vehicles. We can (and should) debate whether it's prudent to plan our cities around them, but I think there's little doubt that we'll see road safety increase dramatically.

Chart via CityLab

Nationwide across the US, transit ridership is only at about 70% of where it was in 2019 before the pandemic. But this is not the case in all cities around the world. According to this recent Bloomberg article, Madrid, Hong Kong, and Paris are all above their 2019 ridership levels. Seoul and Shanghai are also close at just over 90%, and London is at 85%.

So this problem of fewer people riding transit seems to be a North and South American phenomenon. Rio de Janeiro is at 73%, Mexico City is at 70%, and San Francisco is somewhere near or at the bottom at 44%. The obvious explanations for this are that Europe and Asia are generally denser and less car-oriented, their return-to-office patterns have been much stronger (less WFH), and their governments probably care more about transit (and spend more money on it).

Broadly speaking, I think this is all true, but I'd love to know more precisely what's driving these differences. Because it's not exactly obvious. Consider, for example, Paris and London. Paris is at 103% of its 2019 levels, whereas London is only at 85%. Why is that? Both cities share a lot of similarities. They have a river that weaves through the middle, they're dense, they have lots of trains, and both are alpha global cities.

So why the delta? What exactly is Paris doing that is encouraging more transit usage?

Charts via Bloomberg