| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know | 14 | 
                                    
                                    66.7%
                                 | 
| -8 | Refusal | 7 | 
                                    
                                    33.3%
                                 | 
| -7 | Does not apply | 0 | 
                                    
                                    0%
                                 | 
| Sysmiss | 772 |