| Value | Category | Cases | |
|---|---|---|---|
| 0 | no | 3974 |
89.3%
|
| 1 | yes | 457 |
10.3%
|
| 8 | don't know | 15 |
0.3%
|
| 9 | 5 |
0.1%
|
|
| 11 | .Z | 3781 |