| Value | Category | Cases | |
|---|---|---|---|
| 1993 | 1 |
0.2%
|
|
| 1997 | 13 |
3.1%
|
|
| 1998 | 48 |
11.6%
|
|
| 1999 | 106 |
25.5%
|
|
| 2000 | 98 |
23.6%
|
|
| 2001 | 124 |
29.9%
|
|
| 2002 | 25 |
6%
|
|
| Sysmiss | 7634 |