| Value | Category | Cases | |
|---|---|---|---|
| 1997 | 14 |
2.4%
|
|
| 1998 | 94 |
16.4%
|
|
| 1999 | 102 |
17.8%
|
|
| 2000 | 108 |
18.8%
|
|
| 2001 | 144 |
25.1%
|
|
| 2002 | 109 |
19%
|
|
| 2003 | 3 |
0.5%
|
|
| Sysmiss | 425 |