| Value | Category | Cases | |
|---|---|---|---|
| 1 | Full date known | 17 |
6.9%
|
| 2 | Day unknown | 20 |
8.1%
|
| 4 | Day and month unknown | 64 |
25.9%
|
| 8 | Unknown | 146 |
59.1%
|
| 9 | Missing | 0 | |
| Sysmiss | 694 |