| Value | Category | Cases | |
|---|---|---|---|
| 1980 | 1 |
1.4%
|
|
| 1983 | 3 |
4.3%
|
|
| 1984 | 3 |
4.3%
|
|
| 1985 | 5 |
7.2%
|
|
| 1986 | 9 |
13%
|
|
| 1987 | 3 |
4.3%
|
|
| 1988 | 11 |
15.9%
|
|
| 1989 | 7 |
10.1%
|
|
| 1990 | 6 |
8.7%
|
|
| 1991 | 4 |
5.8%
|
|
| 1992 | 4 |
5.8%
|
|
| 1993 | 2 |
2.9%
|
|
| 1994 | 4 |
5.8%
|
|
| 1995 | 1 |
1.4%
|
|
| 1996 | 4 |
5.8%
|
|
| 1997 | 1 |
1.4%
|
|
| 1999 | 1 |
1.4%
|
|
| Sysmiss | 12846 |