| Value | Category | Cases | |
|---|---|---|---|
| 1997 | 1 |
0%
|
|
| 1998 | 56 |
1.6%
|
|
| 1999 | 241 |
6.8%
|
|
| 2000 | 557 |
15.8%
|
|
| 2001 | 1040 |
29.5%
|
|
| 2002 | 1126 |
32%
|
|
| 2003 | 499 |
14.2%
|
|
| Sysmiss | 2480 |