| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -8 | Refusal (spontaneous) | 4 |
0.4%
|
| 3 | 5 |
0.5%
|
|
| 5 | 1 |
0.1%
|
|
| 6 | 1 |
0.1%
|
|
| 7 | 1 |
0.1%
|
|
| 10 | 100 |
9.9%
|
|
| 15 | 66 |
6.5%
|
|
| 20 | 835 |
82.4%
|