| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 380 |
11.5%
|
|
| 2005 | 530 |
16%
|
|
| 2006 | 674 |
20.3%
|
|
| 2007 | 726 |
21.9%
|
|
| 2008 | 915 |
27.6%
|
|
| 2009 | 43 |
1.3%
|
|
| 9997 | Inconsistent | 46 |
1.4%
|
| 9998 | DK | 0 |
0%
|
| Sysmiss | 2765 |