| Value | Category | Cases | |
|---|---|---|---|
| 1980 | 2 |
1.9%
|
|
| 1982 | 1 |
0.9%
|
|
| 1983 | 1 |
0.9%
|
|
| 1985 | 1 |
0.9%
|
|
| 1988 | 2 |
1.9%
|
|
| 1989 | 6 |
5.7%
|
|
| 1990 | 4 |
3.8%
|
|
| 1991 | 5 |
4.7%
|
|
| 1992 | 3 |
2.8%
|
|
| 1993 | 5 |
4.7%
|
|
| 1994 | 11 |
10.4%
|
|
| 1995 | 17 |
16%
|
|
| 1996 | 18 |
17%
|
|
| 1997 | 26 |
24.5%
|
|
| 1998 | 4 |
3.8%
|
|
| Sysmiss | 3304 |