| Value | Category | Cases | |
|---|---|---|---|
| 1989 | 1 |
0.9%
|
|
| 1997 | 1 |
0.9%
|
|
| 1998 | 5 |
4.4%
|
|
| 1999 | 28 |
24.6%
|
|
| 2000 | 45 |
39.5%
|
|
| 2001 | 34 |
29.8%
|
|
| Sysmiss | 11344 |