| Value | Category | Cases | |
|---|---|---|---|
| 1992 | 1 |
2.1%
|
|
| 1997 | 1 |
2.1%
|
|
| 2001 | 1 |
2.1%
|
|
| 2002 | 6 |
12.5%
|
|
| 2003 | 39 |
81.3%
|
|
| Sysmiss | 7977 |