Gotham City has just modified a country-wide legal requirement that the number of legal tenants living in an apartment go from two to four tenants. Most of Gotham City's apartments are 1 or 2 bedrooms. When a recession occurs and average incomes fall, the number of apartments putting up walls in the living room to make room for converted shared rooms goes up. Converted shared apartments reduce rent paid by each tenant. Therefore, though rental delinquency rates tend to rise in economic recessions, finding affordable rental accommodations in Gotham City will not be made more difficult by a recession.
In evaluating the argument, which of the following would be most useful to know?