Each of the judges of the appellate courts of the state resident in the county is authorized to set a salary supplement for his or her secretary over and above the amount of compensation provided in the state budget. The amount of the supplement shall be such that when combined with the compensation provided in the state budget the total salary will not exceed the salary for step E in grade 15 in the general salary schedule for employees of the county in effect when the salary supplement is set. The salary supplement shall be set annually and may be changed by the judge, within the foregoing limits, for year to year, without regard to length of service. Funds for the payment of the salary supplement may be appropriated annually by the county council. (1976 L.M.C., ch. 17, § 1.)