[bluGill]

I'm not an expert in California, but if I understand prop 13 correctly it is possible some of those are people who have lived in SF for many years at the same address - their house is paid off and taxes are minimal so they can afford to live on much less. If your house only costs $400/month to live in ($100 insurance, $100 taxes, $200 other utilities) minimum wage still leaves plenty left over, and presumably if you bought a house 30 years ago you were worth more than minimum wage...

[jaclaz]

Maybe that would account for a part (I am also not at all an expert in California, so it is just speculation), but those cannot reasonably account for 40% of workers.

I mean, if you live in SF and have a yearly income of "only" 50-60,000 US$ working some 2000 hours at 25-30 $/hour, and you live in a house that you can rent for roughly the same amount or that you can sell for (say) a million, what actually keeps you there?

Maybe you can find somewhere else a similar job, paid in the 15-20 $/hour range, you lose 20,000 on the job but get an additional 40,000 from the rent or from interests on the capital.