Data type: PtypInteger32 ([MS-OXCDATA] section 2.11.1)

The PidTagAddressBookSeniorityIndex property<15> ([MS-OXPROPS] section 2.563) contains a signed integer that specifies the seniority order of Address Book objects that represent members of a department and are referenced by a Department object or departmental group, with larger values specifying members that are more senior. It also specifies the sort order of Department objects or departmental groups that represent child departments of another parent department in a hierarchy of departments and that are referenced by the parent's Department object or departmental group, in descending order.