The index was set at 100 for January 2000. San Francisco’s index value of 281 means that prices have surged 181% since January 2000. Every one of the most splendid housing bubbles on this list has or had an index value of over 200, meaning that house prices have at least doubled, either during Housing Bubble 2 or during Housing Bubble 1.
https://wolfstreet.com/2019/10/29/the-most-splendid-housing-bubbles-in-america-october-update/