| Value | Category | Cases | |
|---|---|---|---|
| 1983 | 1 |
2.2%
|
|
| 1986 | 1 |
2.2%
|
|
| 1988 | 1 |
2.2%
|
|
| 1989 | 1 |
2.2%
|
|
| 1990 | 1 |
2.2%
|
|
| 1992 | 3 |
6.7%
|
|
| 1993 | 13 |
28.9%
|
|
| 1994 | 5 |
11.1%
|
|
| 1995 | 8 |
17.8%
|
|
| 1996 | 6 |
13.3%
|
|
| 1997 | 5 |
11.1%
|
|
| Sysmiss | 268 |