| Value | Category | Cases | |
|---|---|---|---|
| 2003 | 1 |
0%
|
|
| 2004 | 68 |
0.9%
|
|
| 2005 | 592 |
7.9%
|
|
| 2006 | 723 |
9.6%
|
|
| 2007 | 743 |
9.9%
|
|
| 2008 | 332 |
4.4%
|
|
| 2009 | 79 |
1.1%
|
|
| 9998 | dk | 17 |
0.2%
|
| 9999 | missing | 2277 |
30.4%
|
| Sysmiss | 2667 |
35.6%
|