Cal. Gov. Code § 31621.9
In counties adopting Section 31676.14, the normal rates of contribution, except for members covered by Article 6.8 (commencing with Section 31639), shall be that which will provide an average annuity at age 55 equal to 1/120 of the final compensation of members not covered by Article 6.8 (commencing with Section 31639), according to the tables adopted by the board of supervisors, for each year of service rendered after entering the system.
This section may be made applicable in counties on the first day of the month after the board of supervisors of the county adopts, by majority vote, a resolution adopting this section.
This section shall apply only to a county of the 10th or 20th class, as provided by Sections 28020, 28031, and 28041.
Ca. Gov. Code § 31621.9