| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 7 |
8.8%
|
| 1945 | 1 |
1.3%
|
|
| 1957 | 1 |
1.3%
|
|
| 1964 | 1 |
1.3%
|
|
| 1991 | 1 |
1.3%
|
|
| 1992 | 1 |
1.3%
|
|
| 1993 | 2 |
2.5%
|
|
| 1994 | 1 |
1.3%
|
|
| 1995 | 3 |
3.8%
|
|
| 1999 | 1 |
1.3%
|
|
| 2002 | 1 |
1.3%
|
|
| 2003 | 4 |
5%
|
|
| 2004 | 2 |
2.5%
|
|
| 2005 | 3 |
3.8%
|
|
| 2006 | 4 |
5%
|
|
| 2007 | 1 |
1.3%
|
|
| 2008 | 4 |
5%
|
|
| 2009 | 1 |
1.3%
|
|
| 2010 | 4 |
5%
|
|
| 2011 | 2 |
2.5%
|
|
| 2012 | 2 |
2.5%
|
|
| 2013 | 3 |
3.8%
|
|
| 2014 | 4 |
5%
|
|
| 2015 | 8 |
10%
|
|
| 2016 | 4 |
5%
|
|
| 2017 | 9 |
11.3%
|
|
| 2018 | 5 |
6.3%
|
|
| Sysmiss | 280 |