Today I learned that Little Caesar's is a bigger pizza chain than Papa John's[1]. As of 2018, the top five are:

1. Domino's, with 14,856 "units" and $12.2 billion in gross sales.

2. Pizza Hut, with 16,784 units and $12.0 billion in gross sales.

3. Little Caesar's, with 5,500 units and $4.0 billion.

4. Papa John's, with 5,199 units and $3.7 billion.

5. California Pizza Kitchen, with 267 units and $840 million.

Everything after Papa John's is a long tail. Strangely, revenue in the long tail is not obviously proportional to the number of units. So instead of a top three, there's really a top two, a next two, and everyone else.

[1] https://pizzatoday.com/pizzeria-rankings/2018-top-100-pizza-...