In addition to other provisions of this Charter, a vacancy shall be deemed to exist in any elective office when any such officer dies, resigns, is removed from office, moves from the City, is convicted of a felony or of misconduct in office under this Charter, is judicially declared to be mentally incompetent, or misses either four (4) consecutive regular Council meetings or twenty-five (25) percent of all regular Council meetings in any calendar year. The Clerk shall be responsible to maintain the record of absences, and shall notify the Council immediately when a vacancy due to absences has occurred.