Cal. Sts. & Hy. Code § 2107.2
Any city or city and county may apply to the Demographic Research Unit of the Department of Finance to estimate its population or the population of any inhabited territory annexed to the city subsequent to the last federal or state census validated by the Demographic Research Unit of the Department of Finance. The department may make the estimate if in the opinion of the department there is available adequate information upon which to base the estimate. The department may develop or contract for the development of additional information if, in the opinion of the department, additional information may make an estimate feasible. Not less than 25 days nor more than 30 days after the completion of the estimate, the Department of Finance shall file a certified copy thereof with the Controller if the estimate is greater than the current certified population.
All apportionments under Section 2107 and all payments under Section 11005 of the Revenue and Taxation Code for any apportionment made beginning with the month following the filing of the estimate shall be based upon the population so estimated until a subsequent estimate is made by the department and a certified copy is filed with the Controller or a subsequent determination is made by the United States Bureau of the Census and a certified copy is filed by the city or city and county with the Controller as provided in Section 2107.1.
The Department of Finance may assess a reasonable charge, not to exceed the actual cost thereof, for the preparation of population estimates pursuant to this section, which is a proper charge against the city or city and county applying therefor. The amount received shall be deposited in the State Treasury as a reimbursement to be credited to the appropriation from which the expenditure is made.
No more than one estimate of its total population shall be filed each fiscal year for each city or city and county.
As of May 1, 1988, any population estimate prepared by the Department of Finance pursuant to Section 2227 of the Revenue and Taxation Code may be used for all purposes of this section unless a written request not to certify is received by the department from the city or city and county within 25 days of completion of the estimate.
Ca. Sts. and High. Code § 2107.2