California Code, Education Code - EDC § 26202

(a) The board shall establish a Gain and Loss Reserve within the Teachers' Retirement Fund for the Cash Balance Benefit Program. The board has sole authority to administer the Gain and Loss Reserve to be drawn upon to the extent necessary to credit interest to employee accounts and employer accounts at the minimum interest rate during years in which the investment earnings of the plan with respect to the Cash Balance Benefit Program are not sufficient for that purpose, and, where necessary, to provide additions to the Annuitant Reserve for monthly annuity payments.

(b) The board shall establish and periodically review goals regarding the sufficiency of the Gain and Loss Reserve based on the recommendation of the actuary.

(c) In the event that the total amount of investment earnings of the plan with respect to the Cash Balance Benefit Program for any plan year exceeds the sum of the total amount required to credit all employee and employer accounts at the minimum interest rate for the plan year plus the administrative costs of the plan with respect to the Cash Balance Benefit Program for the plan year, the board shall determine the amount, if any, that is to be credited to the Gain and Loss Reserve for the plan year. That determination shall be made upon recommendation of the actuary based on the actuarial valuation undertaken following the plan year pursuant to Section 26211 but no later than June 30 following the end of the plan year. In determining whether an amount is to be credited to the Gain and Loss Reserve, the board shall consider the sufficiency of the reserve in light of the goal established for the sufficiency and the recommendations of the actuary.