| Value | Category | Cases | |
|---|---|---|---|
| 1988 | 1 |
0.5%
|
|
| 1994 | 18 |
8.8%
|
|
| 1995 | 10 |
4.9%
|
|
| 1996 | 11 |
5.4%
|
|
| 1997 | 20 |
9.8%
|
|
| 1998 | 18 |
8.8%
|
|
| 1999 | 21 |
10.3%
|
|
| 2000 | 22 |
10.8%
|
|
| 2001 | 48 |
23.5%
|
|
| 2002 | 35 |
17.2%
|
|
| Sysmiss | 248 |