| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 |
0%
|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 0 | 1 |
50%
|
|
| 7 | 1 |
50%
|
|
| Sysmiss | 238 |