| Value | Category | Cases | |
|---|---|---|---|
| 1992 | 1 |
1.7%
|
|
| 1997 | 1 |
1.7%
|
|
| 1999 | 1 |
1.7%
|
|
| 2000 | 3 |
5.2%
|
|
| 2001 | 2 |
3.4%
|
|
| 2005 | 2 |
3.4%
|
|
| 2006 | 2 |
3.4%
|
|
| 2007 | 1 |
1.7%
|
|
| 2008 | 5 |
8.6%
|
|
| 2009 | 40 |
69%
|
|
| Sysmiss | 6227 |