| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 21 |
1.3%
|
| -7 | Does not apply (spontaneous) | 17 |
1%
|
| 1 | Yes | 157 |
9.6%
|
| 2 | No | 1441 |
88.1%
|
| Sysmiss | 27 |