| Value | Category | Cases | |
|---|---|---|---|
| 2000 | 1 |
0.9%
|
|
| 2002 | 16 |
15%
|
|
| 2003 | 16 |
15%
|
|
| 2004 | 19 |
17.8%
|
|
| 2005 | 18 |
16.8%
|
|
| 2006 | 19 |
17.8%
|
|
| 2007 | 18 |
16.8%
|
|
| Sysmiss | 99 |