Cal. Ed. Code § 16720
Each district to which an apportionment or apportionments has been made under this chapter shall repay a portion or all of the principal amount of such apportionment or apportionments and the accrued interest thereon in 30 equal annual payments, as shall be determined by the Controller pursuant to this section. If more than one apportionment is made the annual amount payable shall be the sum of the amounts which would be payable on each apportionment if computed separately.
The Controller shall determine the portion of the principal amount of the apportionment or apportionments made to each district to be repaid by the district by diminishing the principal amount by the product of the ratio which the assessed valuation of the district per unit of average daily attendance of pupils in the grades maintained by the district during the preceding fiscal year bears to the assessed valuation per unit of average daily attendance in the same type of districts in the state and one-half of the principal amount of the apportionment or apportionments, except that the amount to be repaid shall not exceed the amount of the principal apportionment or apportionments.
The Controller shall make the computation to determine the annual repayment due in the next fiscal year following the fiscal year in which the apportionment is made. In any year prior to the 1980-81 fiscal year in which the annual repayment exceeds the amount which may be raised by a three-cent ($0.03) tax rate per one hundred dollars ($100) of assessed valuation in the district, the governing board of the school district shall so certify to the Controller whereupon the Controller shall grant a deferment of the annual repayment which is in excess of the amount that would be produced by a tax rate of three cents ($0.03) per one hundred dollars ($100) of assessed valuation of the district. In any year, beginning with the 1981-82 fiscal year, in which the annual repayment exceeds the amount which may be raised by a levy of 0.0075 percent of the full value in the district, the governing board of the school district shall so certify to the Controller whereupon the Controller shall grant a deferment of the annual repayment which is in excess of the amount that would be produced by a tax of 0.0075 percent of the full value of the district. The amount deferred shall be added to the annual repayment for the next succeeding fiscal year.
Ca. Educ. Code § 16720