| Value | Category | Cases | |
|---|---|---|---|
| 0 | no | 6803 | 
                                    
                                    82.6%
                                 | 
| 1 | yes | 1327 | 
                                    
                                    16.1%
                                 | 
| 8 | don't know | 106 | 
                                    
                                    1.3%
                                 | 
| 9 | 3 | 
                                    
                                    0%
                                 |