| Value | Category | Cases | |
|---|---|---|---|
| 1999 | 1 |
8.3%
|
|
| 2000 | 3 |
25%
|
|
| 2001 | 3 |
25%
|
|
| 2002 | 5 |
41.7%
|
|
| Sysmiss | 8037 |