Of those with a prior residence in the city, 17% said they had lived in San Francisco for less than one year, while 35% said they had been in the city for 10 or more years. The remaining 52% of those respondents said they lived in the city between one and 10 years before becoming homeless."
At least in san francisco it seems its people who lived in SF before becoming homeless that are in the majority.
https://sfstandard.com/public-health/san-francisco-homeless-...