| Value | Category | Cases | |
|---|---|---|---|
| 1987 | 1 |
2.1%
|
|
| 1988 | 1 |
2.1%
|
|
| 1990 | 1 |
2.1%
|
|
| 1991 | 3 |
6.4%
|
|
| 1992 | 3 |
6.4%
|
|
| 1993 | 4 |
8.5%
|
|
| 1994 | 11 |
23.4%
|
|
| 1995 | 2 |
4.3%
|
|
| 1996 | 4 |
8.5%
|
|
| 1997 | 2 |
4.3%
|
|
| 1998 | 8 |
17%
|
|
| 1999 | 6 |
12.8%
|
|
| 2000 | 1 |
2.1%
|
|
| 9997 | inconsistent | 0 |
0%
|
| 9998 | dk | 0 |
0%
|
| Sysmiss | 15938 |