> These articles keep claiming that high rents, mental illness and substance abuse are the causes of the homelessness surge. Zillow's research group looked at

> These articles keep claiming that high rents, mental illness and substance abuse are the causes of the homelessness surge. Zillow's research group looked at the correlation between rent (as a % of income) and homelessness rate. "Homelessness Rises Faster Where Rent Exceeds a Third of Income": https://www.zillow.com/research/homelessness-rent-affordability-22247/ https://www.zillow.com/research/homelessness-rent-affordabil... That's not causality, but it's not nothing. In particular, they found two inflection points: "The first threshold is 22 percent: Any uptick in a community’s rent affordability beyond 22 percent translates into more people experiencing homelessness. The second threshold is 32 percent: Any increase in rent affordability beyond 32 percent leads to a faster-rising rate of homelessness." Obviously both rent and income affect % spent on rent, but reducing or eliminating municipalities' bans on certain housing styles is far simpler than changing the supply of jobs. (Full paper is "Inflection points in community-level homeless rates": https://wp.zillowstatic.com/3/Inflection_Points_20181213-ee1463.pdf https://wp.zillowstatic.com/3/Inflection_Points_20181213-ee1...)