| Value | Category | Cases | |
|---|---|---|---|
| 777 | Don't Know | 0 |
0%
|
| 1992 | 14 |
50%
|
|
| 1993 | 10 |
35.7%
|
|
| 1994 | 4 |
14.3%
|
|
| Sysmiss | 5553 |