| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
1.3%
|
| 1990 | 3 |
4%
|
|
| 1991 | 1 |
1.3%
|
|
| 1998 | 1 |
1.3%
|
|
| 1999 | 1 |
1.3%
|
|
| 2000 | 7 |
9.3%
|
|
| 2002 | 5 |
6.7%
|
|
| 2004 | 1 |
1.3%
|
|
| 2005 | 2 |
2.7%
|
|
| 2006 | 1 |
1.3%
|
|
| 2008 | 1 |
1.3%
|
|
| 2009 | 1 |
1.3%
|
|
| 2010 | 7 |
9.3%
|
|
| 2011 | 2 |
2.7%
|
|
| 2013 | 2 |
2.7%
|
|
| 2014 | 4 |
5.3%
|
|
| 2015 | 6 |
8%
|
|
| 2016 | 5 |
6.7%
|
|
| 2017 | 5 |
6.7%
|
|
| 2018 | 5 |
6.7%
|
|
| 2019 | 5 |
6.7%
|
|
| 2020 | 3 |
4%
|
|
| 2021 | 3 |
4%
|
|
| 2022 | 3 |
4%
|
|
| Sysmiss | 289 |