| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 25 |
4.2%
|
| 0 | 450 |
75.3%
|
|
| 4 | 1 |
0.2%
|
|
| 5 | 3 |
0.5%
|
|
| 7 | 1 |
0.2%
|
|
| 10 | 21 |
3.5%
|
|
| 15 | 1 |
0.2%
|
|
| 20 | 40 |
6.7%
|
|
| 25 | 4 |
0.7%
|
|
| 30 | 25 |
4.2%
|
|
| 40 | 16 |
2.7%
|
|
| 50 | 8 |
1.3%
|
|
| 60 | 1 |
0.2%
|
|
| 70 | 2 |
0.3%
|