| Value | Category | Cases | |
|---|---|---|---|
| 2000 | 1 |
3.3%
|
|
| 2005 | 2 |
6.7%
|
|
| 2006 | 1 |
3.3%
|
|
| 2007 | 9 |
30%
|
|
| 2008 | 17 |
56.7%
|
|
| Sysmiss | 4349 |