| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
2.2%
|
| 2019 | 5 |
5.6%
|
|
| 2020 | 78 |
86.7%
|
|
| 2021 | 5 |
5.6%
|
|
| Sysmiss | 270 |