| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 |
0%
|
| -9 | Don't know (spontaneous) | 3 |
4.9%
|
| 1 | Yes | 13 |
21.3%
|
| 2 | No | 45 |
73.8%
|
| Sysmiss | 164 |