How many people are homeless in San Francisco?
That question is the basis for the most frequent Google search in the city regarding homelessness. The answer, though, is elusive.
Multiple government agencies have attempted to calculate the scope of homelessness, but accurately measuring it or its social and economic impacts is difficult, if not impossible. Homelessness can take many forms and is often a temporary status, making it hard to reliably track.
Read more here: http://projects.sfchronicle.com/sf-homeless/numbers/