| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 258 |
9%
|
|
| 2005 | 510 |
17.9%
|
|
| 2006 | 576 |
20.2%
|
|
| 2007 | 697 |
24.4%
|
|
| 2008 | 729 |
25.5%
|
|
| 2009 | 47 |
1.6%
|
|
| 9997 | Inconsistent | 39 |
1.4%
|
| 9998 | DK | 0 |
0%
|
| Sysmiss | 3223 |