| Value | Category | Cases | |
|---|---|---|---|
| 777 | Don't Know | 0 |
0%
|
| 1993 | 1 |
2.9%
|
|
| 1994 | 1 |
2.9%
|
|
| 1995 | 5 |
14.3%
|
|
| 1996 | 10 |
28.6%
|
|
| 1997 | 12 |
34.3%
|
|
| 1998 | 5 |
14.3%
|
|
| 7777 | 1 |
2.9%
|
|
| Sysmiss | 8363 |