| Value | Category | Cases | |
|---|---|---|---|
| 1981 | 1 |
4.3%
|
|
| 1984 | 1 |
4.3%
|
|
| 1985 | 1 |
4.3%
|
|
| 1986 | 1 |
4.3%
|
|
| 1987 | 2 |
8.7%
|
|
| 1989 | 1 |
4.3%
|
|
| 1991 | 1 |
4.3%
|
|
| 1992 | 2 |
8.7%
|
|
| 1993 | 1 |
4.3%
|
|
| 1995 | 1 |
4.3%
|
|
| 1996 | 1 |
4.3%
|
|
| 1998 | 1 |
4.3%
|
|
| 1999 | 1 |
4.3%
|
|
| 2005 | 1 |
4.3%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9999 | Missing | 7 |
30.4%
|
| Sysmiss | 1434 |