| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 7 |
4.3%
|
| 2000 | 1 |
0.6%
|
|
| 2006 | 2 |
1.2%
|
|
| 2008 | 1 |
0.6%
|
|
| 2009 | 1 |
0.6%
|
|
| 2010 | 4 |
2.5%
|
|
| 2011 | 3 |
1.9%
|
|
| 2012 | 3 |
1.9%
|
|
| 2013 | 4 |
2.5%
|
|
| 2014 | 4 |
2.5%
|
|
| 2015 | 3 |
1.9%
|
|
| 2016 | 2 |
1.2%
|
|
| 2017 | 8 |
4.9%
|
|
| 2018 | 18 |
11.1%
|
|
| 2019 | 9 |
5.6%
|
|
| 2020 | 13 |
8%
|
|
| 2021 | 27 |
16.7%
|
|
| 2022 | 39 |
24.1%
|
|
| 2023 | 13 |
8%
|
|
| Sysmiss | 460 |