| Value | Category | Cases | |
|---|---|---|---|
| 777 | Don't Know | 0 |
0%
|
| 1968 | 2 |
0.5%
|
|
| 1971 | 1 |
0.3%
|
|
| 1972 | 2 |
0.5%
|
|
| 1973 | 1 |
0.3%
|
|
| 1979 | 1 |
0.3%
|
|
| 1986 | 1 |
0.3%
|
|
| 1987 | 1 |
0.3%
|
|
| 1991 | 1 |
0.3%
|
|
| 1992 | 1 |
0.3%
|
|
| 1993 | 3 |
0.8%
|
|
| 1994 | 3 |
0.8%
|
|
| 1995 | 63 |
16.2%
|
|
| 1996 | 146 |
37.5%
|
|
| 1997 | 118 |
30.3%
|
|
| 1998 | 34 |
8.7%
|
|
| 7777 | 9 |
2.3%
|
|
| 9999 | 2 |
0.5%
|
|
| Sysmiss | 8009 |