| Value | Category | Cases | |
|---|---|---|---|
| 777 | Don't Know | 0 |
0%
|
| 1991 | 3 |
1.5%
|
|
| 1992 | 73 |
36.9%
|
|
| 1993 | 61 |
30.8%
|
|
| 1994 | 58 |
29.3%
|
|
| 7777 | 3 |
1.5%
|
|
| Sysmiss | 5383 |