| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 34 |
16.3%
|
| 1955 | 1 |
0.5%
|
|
| 1978 | 1 |
0.5%
|
|
| 1990 | 4 |
1.9%
|
|
| 1991 | 3 |
1.4%
|
|
| 1993 | 1 |
0.5%
|
|
| 1994 | 1 |
0.5%
|
|
| 1995 | 5 |
2.4%
|
|
| 1996 | 3 |
1.4%
|
|
| 1997 | 3 |
1.4%
|
|
| 1998 | 6 |
2.9%
|
|
| 1999 | 2 |
1%
|
|
| 2000 | 9 |
4.3%
|
|
| 2001 | 3 |
1.4%
|
|
| 2002 | 9 |
4.3%
|
|
| 2003 | 7 |
3.3%
|
|
| 2004 | 5 |
2.4%
|
|
| 2005 | 10 |
4.8%
|
|
| 2006 | 5 |
2.4%
|
|
| 2007 | 7 |
3.3%
|
|
| 2008 | 5 |
2.4%
|
|
| 2009 | 6 |
2.9%
|
|
| 2010 | 11 |
5.3%
|
|
| 2011 | 7 |
3.3%
|
|
| 2012 | 10 |
4.8%
|
|
| 2013 | 1 |
0.5%
|
|
| 2014 | 5 |
2.4%
|
|
| 2015 | 8 |
3.8%
|
|
| 2016 | 8 |
3.8%
|
|
| 2017 | 6 |
2.9%
|
|
| 2018 | 9 |
4.3%
|
|
| 2019 | 6 |
2.9%
|
|
| 2020 | 3 |
1.4%
|
|
| 2021 | 2 |
1%
|
|
| 2022 | 2 |
1%
|
|
| 2023 | 1 |
0.5%
|
|
| Sysmiss | 293 |