| Value | Category | Cases | |
|---|---|---|---|
| -2 | Refusal to answer | 6 |
2%
|
| -1 | Don't know | 5 |
1.7%
|
| 0 | 2 |
0.7%
|
|
| 1970 | 1 |
0.3%
|
|
| 1980 | 1 |
0.3%
|
|
| 1986 | 1 |
0.3%
|
|
| 1989 | 1 |
0.3%
|
|
| 1990 | 2 |
0.7%
|
|
| 1991 | 2 |
0.7%
|
|
| 1992 | 1 |
0.3%
|
|
| 1993 | 3 |
1%
|
|
| 1994 | 1 |
0.3%
|
|
| 1995 | 2 |
0.7%
|
|
| 1996 | 4 |
1.4%
|
|
| 1997 | 10 |
3.4%
|
|
| 1998 | 21 |
7.1%
|
|
| 1999 | 30 |
10.2%
|
|
| 2000 | 156 |
52.9%
|
|
| 2001 | 46 |
15.6%
|
|
| Sysmiss | 2338 |