| Value | Category | Cases | |
|---|---|---|---|
| 1990 | 514 |
89.1%
|
|
| 1991 | 15 |
2.6%
|
|
| 1992 | 12 |
2.1%
|
|
| 1993 | 12 |
2.1%
|
|
| 1994 | 5 |
0.9%
|
|
| 1995 | 6 |
1%
|
|
| 1996 | 7 |
1.2%
|
|
| 1997 | 6 |
1%
|
|
| Sysmiss | 344 |