San Francisco Bay Area has one of the most expensive housing markets in the nation. However, as recently as 1970, Bay Area housing was affordable.
Data from the 1970 census shows that a Bay Area family could dedicate 25% to housing and pay off their mortgage in just 13 years. By 1980, a family had to spend 40% of their income to pay off a home mortgage in 30 years; today, it requires 50%. It is precisely government intervention in housing markets which has made previously affordable housing unaffordable. Both the history and the economics of housing show this. —Thomas Sowell