| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
20%
|
| 18 | 1 |
20%
|
|
| 39 | 1 |
20%
|
|
| 61 | 1 |
20%
|
|
| 102 | 1 |
20%
|
|
| Sysmiss | 263 |