| Value | Category | Cases | |
|---|---|---|---|
| 2002 | 2 |
6.3%
|
|
| 2005 | 2 |
6.3%
|
|
| 2006 | 7 |
21.9%
|
|
| 2007 | 21 |
65.6%
|
|
| Sysmiss | 10 |