| Value | Category | Cases | |
|---|---|---|---|
| 1 | Full date known | 4 |
80%
|
| 2 | Day unknown | 0 |
0%
|
| 4 | Day and month unknown | 1 |
20%
|
| 8 | Unknown | 0 |
0%
|
| 9 | Missing | 0 | |
| Sysmiss | 936 |