What amenities and market solutions arise as a city grows

Visiting small towns, this is the rule of thumb I have come across. When a city gets to about 1000 people they develop a small general store which is usually a dollar store (family dollar or dollar general), a post office, a library. Smaller than that they usually do not have those things.

When the city gets to 5000 people they have a real grocery store (rather than a few isles at dollar general) and a real department store, possibly a real hardware superstore. As a city grows larger both the market demand for goods/services grows and the tax base grows allowing more opportunities. I haven’t seen many cities with less than 20-30k people that have public transit. And even those, I haven’t seen ones with public transit trains (as well as a bus system) for less than 200k people.

It seems a city generally has to get to 300-500k+ people to have the fan base and tax revenue to support professional sports team(s). As a city grows certain opportunities arise.

Is there an actual formula for what businesses and public institutions develop relative to population or does it vary wildly by city?

Nothing that considers all variables. Obviously a bedroom suburb isn’t what you’ll think of as a “city of 100,000,” but many are that large. They obviously function very differently from the industrial satellite cities of similar size found near great metropolises. A town of 1000 in ranch country will have a different marketshed than one in rich farmland. Towns that attract middle-class retirees have “mailbox economies” that completely skew the observations.

At any rate, the term you’re seeking for further study is central place theory.

Nice username/post combo there!

thanks for the link. Interesting stuff.