| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 0 | 19 |
76%
|
|
| 50 | 1 |
4%
|
|
| 100 | 5 |
20%
|
|
| Sysmiss | 130 |