| Date | Type | Code | Name |
|---|---|---|---|
| 1977-01-01 | Association merger converted to a simple merger | 55524 → 55573 | Vacon → Void-Vacon |
| 1977-01-01 | Association merger converted to a simple merger | 55573 | Void-Vacon |
| 1972-06-01 | Deletion | 55573 | Void |
| 1972-06-01 | Association merger | 55524 → 55573 | Vacon → Void-Vacon |
| 1972-06-01 | Association merger | 55573 | Void → Void-Vacon |
| 1943-01-01 | Creation | 55573 | Void |