| Value | Category | Cases | |
|---|---|---|---|
| 1980 | 1 |
0.3%
|
|
| 1984 | 1 |
0.3%
|
|
| 1986 | 2 |
0.7%
|
|
| 1993 | 47 |
15.7%
|
|
| 1994 | 4 |
1.3%
|
|
| 1995 | 21 |
7%
|
|
| 1996 | 123 |
41.1%
|
|
| 1997 | 100 |
33.4%
|
|
| Sysmiss | 14 |