| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 |
0%
|
| -9 | Don't know (spontaneous) | 1 |
0.5%
|
| 1 | Yes | 14 |
6.8%
|
| 2 | No | 191 |
92.7%
|
| Sysmiss | 495 |