| Value | Category | Cases | |
|---|---|---|---|
| -2 | Refusal to answer | 0 |
0%
|
| -1 | Don't know | 1 |
1.9%
|
| 0 | 3 |
5.6%
|
|
| 1964 | 1 |
1.9%
|
|
| 1980 | 1 |
1.9%
|
|
| 1985 | 1 |
1.9%
|
|
| 1988 | 1 |
1.9%
|
|
| 1989 | 1 |
1.9%
|
|
| 1990 | 3 |
5.6%
|
|
| 1991 | 1 |
1.9%
|
|
| 1992 | 1 |
1.9%
|
|
| 1993 | 5 |
9.3%
|
|
| 1994 | 1 |
1.9%
|
|
| 1995 | 2 |
3.7%
|
|
| 1996 | 2 |
3.7%
|
|
| 1997 | 3 |
5.6%
|
|
| 1998 | 8 |
14.8%
|
|
| 1999 | 7 |
13%
|
|
| 2000 | 7 |
13%
|
|
| 2001 | 5 |
9.3%
|
|
| Sysmiss | 2579 |