| Value | Category | Cases | |
|---|---|---|---|
| 0 | no | 1425 | 
                                                                 
                                    
                                    8.2%
                                 
                                                             | 
                                                        
                    
| 1 | yes | 10921 | 
                                                                 
                                    
                                    62.9%
                                 
                                                             | 
                                                        
                    
| 8 | don't know | 5016 | 
                                                                 
                                    
                                    28.9%
                                 
                                                             | 
                                                        
                    
| 9 | 1 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 11 | .Z | 1391 |