| Value | Category | Cases | |
|---|---|---|---|
| 1997 | 1 |
6.3%
|
|
| 1998 | 2 |
12.5%
|
|
| 1999 | 8 |
50%
|
|
| 2000 | 5 |
31.3%
|
|
| Sysmiss | 11628 |