| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 |
0%
|
| -9 | Don't know (spontaneous) | 4 |
0.7%
|
| -7 | Does not apply | 16 |
2.7%
|
| 1 | Yes | 71 |
11.9%
|
| 2 | No | 506 |
84.8%
|
| Sysmiss | 104 |