| Value | Category | Cases | |
|---|---|---|---|
| -2 | Refusal to answer | 1 |
3.2%
|
| -1 | Don't know | 1 |
3.2%
|
| 0 | 20 |
64.5%
|
|
| 10 | 1 |
3.2%
|
|
| 12 | 2 |
6.5%
|
|
| 18 | 1 |
3.2%
|
|
| 20 | 2 |
6.5%
|
|
| 30 | 1 |
3.2%
|
|
| 51 | 1 |
3.2%
|
|
| 60 | 1 |
3.2%
|