Doesn’t that depend on the age of the building? I thought rent control was 1970s and earlier? That being said, SF is generally very tenant/sub tenant friendly in its laws.
https://smartasset.com/mortgage/price-to-rent-ratio-50-large...
They've made more money from appreciation than from rising rents.
Appreciation, by itself, will naturally drive this ratio down because of rent control laws. The value of the home is the denominator in that fraction.