| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 142 |
1.9%
|
|
| 2005 | 761 |
10.1%
|
|
| 2006 | 840 |
11.2%
|
|
| 2007 | 875 |
11.7%
|
|
| 2008 | 929 |
12.4%
|
|
| 2009 | 369 |
4.9%
|
|
| 9998 | dk | 5 |
0.1%
|
| 9999 | missing | 836 |
11.1%
|
| Sysmiss | 2742 |
36.6%
|