Let's say you bought a home several years ago for $100,000. The Assessor determined that the purchase price was the fair market value, so the new base year value of the property was set at $100,000.
California Revenue and Taxation Code Section 51(a)(2)
A Proposition 8 reduction is a form of assessment relief. It may be applied by the Assessor when a property's assessed value exceeds the current market value. By the end of June all Santa Clara County property owners receive notification of their assessed value.
Allows property owners, under certain circumstances, to temporarily reduce the assessed value when the market value of their property drops below the Assessed Value due to damage by misfortune or calamity (e.g. fire, earthquake, etc.).