4. The European Data Protection Supervisor shall be assisted by a secretariat. The officials and other staff members of the secretariat shall be appointed by the European Data Protection Supervisor and their superior shall be the European Data Protection Supervisor. They shall be subject exclusively to his or her direction. Their numbers shall be decided each year as part of the budgetary procedure. Article 75(2) of Regulation (EU) 2016/679 shall apply to the staff of the European Data Protection Supervisor involved in carrying out the tasks conferred on the European Data Protection Board by Union law.