| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 7 |
5.7%
|
| 1997 | 1 |
0.8%
|
|
| 2000 | 2 |
1.6%
|
|
| 2003 | 1 |
0.8%
|
|
| 2010 | 2 |
1.6%
|
|
| 2014 | 1 |
0.8%
|
|
| 2015 | 2 |
1.6%
|
|
| 2017 | 2 |
1.6%
|
|
| 2018 | 5 |
4.1%
|
|
| 2019 | 5 |
4.1%
|
|
| 2020 | 13 |
10.6%
|
|
| 2021 | 14 |
11.4%
|
|
| 2022 | 46 |
37.4%
|
|
| 2023 | 22 |
17.9%
|
|
| Sysmiss | 228 |