| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 11 | 1 |
20%
|
|
| 20 | 1 |
20%
|
|
| 25 | 1 |
20%
|
|
| 38 | 1 |
20%
|
|
| 99 | 1 |
20%
|
|
| Sysmiss | 724 |