| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 202 |
2.7%
|
|
| 2005 | 741 |
9.9%
|
|
| 2006 | 799 |
10.7%
|
|
| 2007 | 830 |
11.1%
|
|
| 2008 | 312 |
4.2%
|
|
| 2009 | 99 |
1.3%
|
|
| 9998 | dk | 12 |
0.2%
|
| 9999 | missing | 1885 |
25.1%
|
| Sysmiss | 2619 |
34.9%
|