I think the number I read was at least 30% of homeless have mental issues. Another large group is addicted but that can also be a mental health issueQuite a few years ago the state of Michigan got out of the mental health care business by closing all the state run mental hospitals. A dear friend of mine had been an orderly at the hospital in Traverse City. It was a huge facility, with dairy and crop farms where the patients worked. I asked him once what happened to all the people who were patients when the place closed down. He said, "The State relocated them. They either live under bridges or are dead". He would often see former patients in the obituaries.
I think you could add, or in jail. A friend up here works at the prison and he says a good number of the people there are probably not so much criminals as people with mental health issues. But we no longer have anyplace to put them, so they end up in jail.