| Value | Category | Cases | |
|---|---|---|---|
| 99 | Mising | 0 |
0%
|
| 1984 | 1 |
2.8%
|
|
| 1988 | 28 |
77.8%
|
|
| 1990 | 1 |
2.8%
|
|
| 1991 | 1 |
2.8%
|
|
| 1993 | 1 |
2.8%
|
|
| 1994 | 1 |
2.8%
|
|
| 1995 | 1 |
2.8%
|
|
| 1996 | 1 |
2.8%
|
|
| 2009 | 1 |
2.8%
|
|
| Sysmiss | 1689 |