| Value | Category | Cases | |
|---|---|---|---|
| -2 | Refusal to answer | 0 |
0%
|
| -1 | Don't know | 1 |
1%
|
| 1974 | 1 |
1%
|
|
| 1981 | 1 |
1%
|
|
| 1982 | 2 |
2.1%
|
|
| 1983 | 3 |
3.1%
|
|
| 1985 | 2 |
2.1%
|
|
| 1986 | 1 |
1%
|
|
| 1988 | 1 |
1%
|
|
| 1989 | 2 |
2.1%
|
|
| 1990 | 2 |
2.1%
|
|
| 1992 | 2 |
2.1%
|
|
| 1993 | 1 |
1%
|
|
| 1995 | 3 |
3.1%
|
|
| 1996 | 13 |
13.4%
|
|
| 1997 | 6 |
6.2%
|
|
| 1998 | 17 |
17.5%
|
|
| 1999 | 17 |
17.5%
|
|
| 2000 | 20 |
20.6%
|
|
| 2001 | 2 |
2.1%
|
|
| Sysmiss | 7752 |