| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 325 |
10.4%
|
|
| 2005 | 529 |
16.9%
|
|
| 2006 | 641 |
20.5%
|
|
| 2007 | 717 |
23%
|
|
| 2008 | 816 |
26.1%
|
|
| 2009 | 54 |
1.7%
|
|
| 9997 | Inconsistent | 40 |
1.3%
|
| 9998 | DK | 0 |
0%
|
| Sysmiss | 2957 |