| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not given | 241 |
94.1%
|
| 44 | Marked on card - no date given | 4 |
1.6%
|
| 66 | Reported by mother | 9 |
3.5%
|
| 99 | Missing | 2 |
0.8%
|