| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 274 | 
                                                                 
                                    
                                    4%
                                 
                                                             | 
                                                        
                    
| 1 | Yes | 1136 | 
                                                                 
                                    
                                    16.7%
                                 
                                                             | 
                                                        
                    
| 2 | No | 5389 | 
                                                                 
                                    
                                    79.3%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 3873 |