| Value | Category | Cases | |
|---|---|---|---|
| 1 | Full date known | 7 |
35%
|
| 2 | Day unknown | 0 |
0%
|
| 4 | Day and month unknown | 7 |
35%
|
| 8 | Unknown | 6 |
30%
|
| 9 | Missing | 0 | |
| Sysmiss | 921 |