| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.3%
|
| 1993 | 1 |
0.3%
|
|
| 1998 | 1 |
0.3%
|
|
| 2001 | 1 |
0.3%
|
|
| 2003 | 1 |
0.3%
|
|
| 2005 | 1 |
0.3%
|
|
| 2006 | 1 |
0.3%
|
|
| 2007 | 5 |
1.5%
|
|
| 2008 | 3 |
0.9%
|
|
| 2009 | 3 |
0.9%
|
|
| 2011 | 3 |
0.9%
|
|
| 2012 | 1 |
0.3%
|
|
| 2013 | 12 |
3.5%
|
|
| 2014 | 2 |
0.6%
|
|
| 2015 | 6 |
1.8%
|
|
| 2016 | 11 |
3.2%
|
|
| 2017 | 15 |
4.4%
|
|
| 2018 | 20 |
5.8%
|
|
| 2019 | 34 |
9.9%
|
|
| 2020 | 42 |
12.3%
|
|
| 2021 | 70 |
20.5%
|
|
| 2022 | 99 |
28.9%
|
|
| 2023 | 9 |
2.6%
|
|
| Sysmiss | 240 |