| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 419 |
5.6%
|
|
| 2005 | 799 |
10.7%
|
|
| 2006 | 890 |
11.9%
|
|
| 2007 | 994 |
13.3%
|
|
| 2008 | 964 |
12.9%
|
|
| 2009 | 422 |
5.6%
|
|
| 9999 | missing | 183 |
2.4%
|
| Sysmiss | 2828 |
37.7%
|