| Value | Category | Cases | |
|---|---|---|---|
| 1983 | 1 |
4%
|
|
| 1987 | 1 |
4%
|
|
| 1992 | 1 |
4%
|
|
| 1993 | 8 |
32%
|
|
| 1994 | 8 |
32%
|
|
| 1995 | 4 |
16%
|
|
| 1996 | 2 |
8%
|
|
| Sysmiss | 278 |