| Value | Category | Cases | |
|---|---|---|---|
| 1992 | 1 |
0.4%
|
|
| 1993 | 10 |
4%
|
|
| 1994 | 33 |
13%
|
|
| 1995 | 36 |
14.2%
|
|
| 1996 | 50 |
19.8%
|
|
| 1997 | 120 |
47.4%
|
|
| 1998 | 3 |
1.2%
|
|
| Sysmiss | 10103 |