| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
0.1%
|
| -7 | Does not apply (spontaneous) | 618 |
6.6%
|
| 1 | Yes | 4507 |
48.1%
|
| 2 | No | 4246 |
45.3%
|