Gov. Code, § 31808.8

The board of supervisors of a county of the third class may, by majority vote, adopt a resolution providing either or both of the following:

(a) That subdivision (b) of Section 31808 is applicable to persons who become members of the county retirement system after the effective date designated in the resolution and that persons who were subject to subdivision (a) of Section 31808 prior to that date may elect to have their retirement allowance for services rendered after that date computed in accordance with subdivision (b) of Section 31808.

(b) That an employee who is subject to subdivision (a) of Section 31808.7 may elect to have his retirement allowance computed, with respect to service rendered after the effective date designated in the resolution, in accordance with the following:

(1) The fraction of one seventy-fifth of the first one thousand fifty dollars ($1,050) monthly of the member’s final compensation set forth in the table appearing in Section 31676.12 in the column applicable to his age at retirement taken to the preceding completed quarter year multiplied by the number of years of creditable service as provided therein.

(2) The fraction of one-fiftieth of any remaining portion of the member’s final compensation set forth in the table appearing in Section 31676.12 in the column applicable to his age at retirement taken to the preceding completed quarter year multiplied by the number of years of creditable service.