| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 116 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    
| 1 | Yes | 913 | 
                                                                 
                                    
                                    15.2%
                                 
                                                             | 
                                                        
                    
| 2 | No | 4974 | 
                                                                 
                                    
                                    82.9%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 4669 |