According to the latest biannual census of the city's homeless by the SF Human Services Agency, there are 6,514 homeless living in the city, an overall increase of 2% since 2007. 78% surveyed said they were living in the city when they became homeless -- up from 62% two years ago, which homeless advocates point to as proving that it is not necessarily true that the city is a homeless magnet.

Jennifer Friedenbach of the Coalition on Homelessness says:

"Oftentimes, public officials use the magnet theory as an escape valve for not having to address the homeless issue, saying, 'If we address it, more will come.' The truth is, we've got millions of Americans who are homeless, and we need to address it and stop playing these kinds of games with numbers."

Gavin's people are still saying 22% is still "a big chunk."

According to a demographic survey conducted one month later, only 3% said mental health issues were a primary cause of their being homeless, and 15% cited alcohol and drugs as primary factors.

The census was taken over the course of one night in January, when the majority of homeless (3,805 of the 6,514) were not on the streets but in a jail, shelter or hospital. The info on where everyone had come from are from a February survey of 534 people -- all of whom were, presumably, sober and sane enough to respond to a set of survey questions.