| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 |
0%
|
| -9 | Don't know (spontaneous) | 1 |
0.5%
|
| -7 | 9 |
4.5%
|
|
| 1 | Yes | 36 |
18.1%
|
| 2 | No | 153 |
76.9%
|
| Sysmiss | 146 |