| Value | Category | Cases | |
|---|---|---|---|
| 1998 | 1 |
12.5%
|
|
| 1999 | 2 |
25%
|
|
| 2000 | 1 |
12.5%
|
|
| 2001 | 1 |
12.5%
|
|
| 2002 | 3 |
37.5%
|
|
| Sysmiss | 142 |