| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
0.1%
|
| -7 | Does not apply (spontaneous) | 605 |
6.5%
|
| 1 | Yes | 4691 |
50%
|
| 2 | No | 4075 |
43.5%
|