| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 23 |
3.8%
|
| 1 | Above 90% | 25 |
4.1%
|
| 2 | Between 50% and 90% | 111 |
18.3%
|
| 3 | Below 50% | 448 |
73.8%
|
| Sysmiss | 693 |