| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not given | 528 |
2.9%
|
| 2009 | 1 |
0%
|
|
| 2010 | 11 |
0.1%
|
|
| 2011 | 346 |
1.9%
|
|
| 2012 | 917 |
5.1%
|
|
| 2013 | 1428 |
7.9%
|
|
| 2014 | 524 |
2.9%
|
|
| 4444 | Marked on card | 59 |
0.3%
|
| Sysmiss | 14294 |
78.9%
|