The director of personnel shall obtain, rate, and preserve the records of individual efficiency of all persons holding positions under this part. Such ratings shall be submitted on forms prescribed by the director of personnel and shall be made by the department heads or their supervising officers or both in accordance with regulations prescribed by the personnel board. Such efficiency ratings shall constitute grounds for: Increase in the rate of compensation for employees who have not attained the maximum rate for the class to which their positions are allotted; continuance at the existing rate of compensation without increase or decrease; decrease in the rate of compensation for the employees who are receiving more than the minimum rate for the class to which their positions are allocated; promotion, demotion, layoff, transfer, or dismissal.