| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
2.6%
|
| 0 | None | 17 |
44.7%
|
| 1 | 2 |
5.3%
|
|
| 2 | 8 |
21.1%
|
|
| 3 | 1 |
2.6%
|
|
| 5 | 2 |
5.3%
|
|
| 10 | 5 |
13.2%
|
|
| 20 | 2 |
5.3%
|
|
| Sysmiss | 354 |