| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 26 |
4.3%
|
| 0 | 568 |
95%
|
|
| 50 | 1 |
0.2%
|
|
| 70 | 1 |
0.2%
|
|
| 80 | 1 |
0.2%
|
|
| 100 | 1 |
0.2%
|