| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 12 |
1.5%
|
| 1974 | 1 |
0.1%
|
|
| 1990 | 1 |
0.1%
|
|
| 1995 | 1 |
0.1%
|
|
| 1996 | 1 |
0.1%
|
|
| 1998 | 1 |
0.1%
|
|
| 1999 | 2 |
0.2%
|
|
| 2000 | 5 |
0.6%
|
|
| 2002 | 1 |
0.1%
|
|
| 2003 | 1 |
0.1%
|
|
| 2004 | 1 |
0.1%
|
|
| 2005 | 1 |
0.1%
|
|
| 2006 | 1 |
0.1%
|
|
| 2008 | 4 |
0.5%
|
|
| 2009 | 1 |
0.1%
|
|
| 2010 | 8 |
1%
|
|
| 2011 | 4 |
0.5%
|
|
| 2012 | 5 |
0.6%
|
|
| 2013 | 10 |
1.2%
|
|
| 2014 | 7 |
0.9%
|
|
| 2015 | 7 |
0.9%
|
|
| 2016 | 9 |
1.1%
|
|
| 2017 | 9 |
1.1%
|
|
| 2018 | 41 |
5%
|
|
| 2019 | 23 |
2.8%
|
|
| 2020 | 161 |
19.7%
|
|
| 2021 | 151 |
18.5%
|
|
| 2022 | 277 |
33.9%
|
|
| 2023 | 71 |
8.7%
|
|
| Sysmiss | 170 |