| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 198 |
2.6%
|
|
| 2005 | 695 |
9.3%
|
|
| 2006 | 748 |
10%
|
|
| 2007 | 840 |
11.2%
|
|
| 2008 | 952 |
12.7%
|
|
| 2009 | 369 |
4.9%
|
|
| 9998 | dk | 5 |
0.1%
|
| 9999 | missing | 986 |
13.1%
|
| Sysmiss | 2706 |
36.1%
|