| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
2.1%
|
| 2005 | 1 |
2.1%
|
|
| 2009 | 1 |
2.1%
|
|
| 2013 | 2 |
4.3%
|
|
| 2015 | 1 |
2.1%
|
|
| 2016 | 1 |
2.1%
|
|
| 2017 | 3 |
6.4%
|
|
| 2018 | 4 |
8.5%
|
|
| 2019 | 2 |
4.3%
|
|
| 2020 | 3 |
6.4%
|
|
| 2021 | 8 |
17%
|
|
| 2022 | 14 |
29.8%
|
|
| 2023 | 6 |
12.8%
|
|
| Sysmiss | 56 |