| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 |
6.3%
|
| 1998 | 1 |
1%
|
|
| 2011 | 1 |
1%
|
|
| 2013 | 1 |
1%
|
|
| 2017 | 2 |
2.1%
|
|
| 2018 | 8 |
8.3%
|
|
| 2019 | 12 |
12.5%
|
|
| 2020 | 7 |
7.3%
|
|
| 2021 | 15 |
15.6%
|
|
| 2022 | 34 |
35.4%
|
|
| 2023 | 9 |
9.4%
|
|
| Sysmiss | 258 |