| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not given | 24 |
3.1%
|
| 1 | 1 |
0.1%
|
|
| 11 | 1 |
0.1%
|
|
| 17 | 2 |
0.3%
|
|
| 21 | 1 |
0.1%
|
|
| 22 | 1 |
0.1%
|
|
| 29 | 1 |
0.1%
|
|
| 44 | Marked on card - no date | 41 |
5.3%
|
| 66 | Reported by mother | 88 |
11.4%
|
| 97 | Missing | 610 |
79.2%
|
| Sysmiss | 1934 |