| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 17 |
58.6%
|
| 1924 | 1 |
3.4%
|
|
| 1990 | 1 |
3.4%
|
|
| 1997 | 1 |
3.4%
|
|
| 2001 | 1 |
3.4%
|
|
| 2004 | 2 |
6.9%
|
|
| 2013 | 1 |
3.4%
|
|
| 2019 | 1 |
3.4%
|
|
| 2021 | 2 |
6.9%
|
|
| 2023 | 2 |
6.9%
|
|
| Sysmiss | 116 |