| Value | Category | Cases | |
|---|---|---|---|
| 1990 | 72 |
66.1%
|
|
| 1991 | 8 |
7.3%
|
|
| 1992 | 4 |
3.7%
|
|
| 1993 | 6 |
5.5%
|
|
| 1994 | 8 |
7.3%
|
|
| 1995 | 3 |
2.8%
|
|
| 1996 | 5 |
4.6%
|
|
| 1997 | 3 |
2.8%
|
|
| Sysmiss | 812 |