| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
20%
|
| 1 | 1 |
20%
|
|
| 4 | 1 |
20%
|
|
| 6 | 1 |
20%
|
|
| 12 | 1 |
20%
|
|
| Sysmiss | 356 |