| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 16 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    
| 1 | Yes | 3726 | 
                                                                 
                                    
                                    34.9%
                                 
                                                             | 
                                                        
                    
| 2 | No | 6930 | 
                                                                 
                                    
                                    64.9%
                                 
                                                             |