| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not given | 1359 |
7.5%
|
| 2010 | 8 |
0%
|
|
| 2011 | 149 |
0.8%
|
|
| 2012 | 704 |
3.9%
|
|
| 2013 | 1135 |
6.3%
|
|
| 2014 | 423 |
2.3%
|
|
| 4444 | Marked on card | 36 |
0.2%
|
| Sysmiss | 14294 |
78.9%
|