Cal. Gov. Code § 51510

Annually on or before the third Monday in August, the county auditor shall transmit to the city legislative body a written statement, showing separately the total value of all property within the city and the total value of all property in each district or portion of the city in which a different rate of taxation is to be levied. The value shall be ascertained from the assessment books of the county for the year, as equalized and corrected.