| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 17 |
4.7%
|
| 0 | 336 |
93.3%
|
|
| 5 | 1 |
0.3%
|
|
| 10 | 1 |
0.3%
|
|
| 15 | 1 |
0.3%
|
|
| 20 | 1 |
0.3%
|
|
| 30 | 1 |
0.3%
|
|
| 40 | 1 |
0.3%
|
|
| 50 | 1 |
0.3%
|