| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 17 |
8.9%
|
|
| 2005 | 26 |
13.6%
|
|
| 2006 | 40 |
20.9%
|
|
| 2007 | 35 |
18.3%
|
|
| 2008 | 67 |
35.1%
|
|
| 2009 | 3 |
1.6%
|
|
| 9997 | Inconsistent | 3 |
1.6%
|
| 9998 | DK | 0 |
0%
|
| Sysmiss | 5888 |