| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
5%
|
| 7 | 8 |
40%
|
|
| 8 | 1 |
5%
|
|
| 10 | 2 |
10%
|
|
| 12 | 1 |
5%
|
|
| 20 | 3 |
15%
|
|
| 30 | 3 |
15%
|
|
| 40 | 1 |
5%
|
|
| Sysmiss | 344 |