| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not given | 2780 |
15.4%
|
| 2011 | 14 |
0.1%
|
|
| 2012 | 63 |
0.3%
|
|
| 2013 | 615 |
3.4%
|
|
| 2014 | 334 |
1.8%
|
|
| 4444 | Marked on card | 8 |
0%
|
| Sysmiss | 14294 |
78.9%
|