The high cost of living likely accounts for what some perceive to be a "Bay Area exodus." It's hard to quantify such a trend with limited census data, but multiple reports imply Bay Area residents are at least thinking about leaving.
For a family of four, $117,400 a year in San Francisco County is considered low income, and I totally believe that. The thing about living in the Bay Area is that it really feels like you just can’t get ahead there. It’s dirty, dangerous, and everyday going downtown you will be witness to the horrific situation the cities most vulnerable (homeless) are in.
I wouldn’t be surprised at all to hear people are leaving because who wants to live in a place like that.