| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
5.7%
|
| 1964 | 1 |
1.1%
|
|
| 1992 | 1 |
1.1%
|
|
| 1996 | 1 |
1.1%
|
|
| 1999 | 1 |
1.1%
|
|
| 2000 | 4 |
4.6%
|
|
| 2001 | 1 |
1.1%
|
|
| 2002 | 1 |
1.1%
|
|
| 2004 | 1 |
1.1%
|
|
| 2005 | 3 |
3.4%
|
|
| 2006 | 2 |
2.3%
|
|
| 2007 | 2 |
2.3%
|
|
| 2008 | 3 |
3.4%
|
|
| 2009 | 2 |
2.3%
|
|
| 2010 | 2 |
2.3%
|
|
| 2012 | 1 |
1.1%
|
|
| 2013 | 4 |
4.6%
|
|
| 2014 | 1 |
1.1%
|
|
| 2015 | 4 |
4.6%
|
|
| 2016 | 5 |
5.7%
|
|
| 2017 | 4 |
4.6%
|
|
| 2018 | 6 |
6.9%
|
|
| 2019 | 6 |
6.9%
|
|
| 2020 | 10 |
11.5%
|
|
| 2021 | 6 |
6.9%
|
|
| 2022 | 10 |
11.5%
|
|
| Sysmiss | 288 |