| Value | Category | Cases | |
|---|---|---|---|
| 1985 | 9 |
8.7%
|
|
| 1987 | 3 |
2.9%
|
|
| 1990 | 11 |
10.6%
|
|
| 1992 | 5 |
4.8%
|
|
| 1993 | 7 |
6.7%
|
|
| 1995 | 12 |
11.5%
|
|
| 2000 | 3 |
2.9%
|
|
| 2008 | 4 |
3.8%
|
|
| 2011 | 20 |
19.2%
|
|
| 2012 | 9 |
8.7%
|
|
| 2013 | 15 |
14.4%
|
|
| 9998 | don't know | 6 |
5.8%
|
| Sysmiss | 16326 |