[tlb]

What precisely does "X% of people in an metropolitan statistical area cannot afford local rent?" mean?

Aren't all those people paying rent now? If not, in what sense are they "in" an area? If so, in what sense can they not "afford" it?

A large category of people not paying rent is homeowners. Retired homeowners might have small incomes that suggest they can't afford rent, but because they own their home they are fine. Are they part of X%?

What is "local rent"? Perhaps they mean an average of the area. If so, it's not surprising that a good fraction can't afford the average rent, so they live in below-average apartments. Any healthy housing market would have this.

What is "afford"? Is there some percentage of income they're assumed to be able to pay as rent? If some people decide to spend a higher percentage of their income on rent because they care about their neighborhood more than eating out or buying gadgets, do they belong in a statistic that seems designed to show how unaffordable housing is?

I imagine one could write definitions of the above terms to get X anywhere from 0% to 100%.