You look at numbers like this  and you go: Whoa. The rent really, really is too damn high. Median rent in San Francisco is now over $3,000 a month. WHo can pay that? Seriously.
The federal government says your rent payment shouldn't be more than a third of your income. That means to qualify for the median -- not the highest, but the median -- rent in this town, you need to be earning $9,000 a month, or $108,000 a year. That is NOT, by any standard, the median income in town.
So let's say you spend half your income on rent. You still have to make $72,000 to afford the median apartment. Crazy stuff. And when local politicians say they support "rent control," that's nice but it's not the point. Controlling rent at $3,000 a month doesn't make the city affordable.
If rent controls applied to vacant apartments, then rents overall, across the city, would rise at the level of inflation -- and people on fixed incomes (social security, disability, SSI) would be able to keep pace. You want to know why there are so many homeless people in this city? One reason: Two decades ago, SSI paid enough every month to cover the cost of an apartment and leave enough to buy clothes and eat. Now, it doesn't pay enough for an SRO hotel, even if you don't buy anything else.
So people wind up on the street.