| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not given | 110 |
1.6%
|
| 2013 | 1 |
0%
|
|
| 2014 | 240 |
3.4%
|
|
| 2015 | 490 |
7%
|
|
| 2016 | 730 |
10.4%
|
|
| 2017 | 13 |
0.2%
|
|
| 4444 | Marked on card | 24 |
0.3%
|
| 6666 | Mother reported | 23 |
0.3%
|
| 9997 | Inconsistent | 4 |
0.1%
|
| Sysmiss | 5370 |
76.7%
|