| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
0.1%
|
| -7 | Does not apply (spontaneous) | 464 |
4.9%
|
| 1 | Yes | 4490 |
47.9%
|
| 2 | No | 4417 |
47.1%
|