| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 11 |
0.1%
|
| -7 | Does not apply (spontaneous) | 784 |
8.4%
|
| 1 | Yes | 4150 |
44.3%
|
| 2 | No | 4431 |
47.3%
|