"Only 10 percent of California's 7 million plus homeowners have earthquake insurance – and the number has dropped by more than half since the deadly quake" (2014) You can get an estimate for an earthquake insurance policy with the California Earthquake Authority. [1] https://www.nbcnews.com/news/investigations/why-do-so-few-ca... [2] https://www.earthquakeauthority.com/
Most insurance companies bailed out of the business of earthquake insurance after Northridge because when it happens, the claims are enormous. The 1906 San Francisco Earthquake was an indirect factor that lead to the Panic of 1907 due to the high volume of insurance claims.
[1]https://www.marketwatch.com/story/25-years-after-bay-area-qu...