California Code, Revenue and Taxation Code - RTC § 755

(a) On or before July 15, the board shall transmit to each county auditor an estimate of the total unitary value and operating nonunitary value of state-assessed property in the county and of nonunitary state-assessed property in each revenue district in the county.  An estimate need not be made for a revenue district that did not levy a tax or assessment during the preceding year unless the board receives on or before January 1 preceding the fiscal year for which the levy is to be made a notice in writing of the proposed levy.  The estimate shall be regarded as establishing the total assessed value of state-assessed property in the county and each revenue district in the county for the purpose of determining tax rates, subject only to those changes as may be transmitted on or prior to July 31.  All information furnished pursuant to this section is at all times during office hours open to inspection by any interested person or entity.

(b) Notwithstanding subdivision (a), in making the estimate referred to in subdivision (a), the value of property described in paragraph (1) of subdivision (a) of Section 100.1 and the nonunitary value of the property of regulated railway companies, property subject to subdivisions (i), (j), (k), and (l) of Section 100, and property subject to Section 100.9 shall be allocated by revenue district.

(c) The amendments made to this section by the act  1 that added this subdivision apply for the 2007-08 fiscal year and for each fiscal year thereafter.