Co-authored by Jens von Bergmann and cross-posted at MountainMath

Are people liquids or solids?

Trick question: they’re kind of both. This matters in terms of how we track people and project their location forward in time. There are basic demographic methods that effectively take people as solids. We can see where they are now. We can see how they’ve been moving recently. We can age them forward in time, including adding new little people and imagining older people dying off. And we can project forward how many people we’ll have in the future.

But people are also liquid. They slosh around a bit, but they eventually tend to settle downhill into the places where there are containers for them. Here our best bet in terms of projecting people’s location forward in time is to figure out the lay of the land and where the most likely containers are going to be located.

Sometimes our liquid and solid projections match up ok. But other times they don’t. Let’s make this discussion a little more solid by zooming in to take a look at a potential divergence in projections right here in Metro Vancouver.

When – if ever – will suburban Surrey surpass the population of the City of Vancouver?

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