Cal. Gov. Code § 19992.8

After consultation with appointing powers and other supervising officials the department shall assist and encourage state agencies to establish standards of performance for managerial employees and may provide training in developing performance appraisal systems. Such standards shall be mutually developed by managerial employees and their appointing powers. These standards shall be based on individual and organizational requirements established, in writing, for the reporting period. The reporting period shall be no more than 12 months from the date of the last report following the end of the employee’s probationary period.