| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 | 
                                    
                                    0.3%
                                 | 
| -7 | Does not apply (sponatneous) | 9 | 
                                    
                                    0.9%
                                 | 
| 1 | Yes | 453 | 
                                    
                                    44.2%
                                 | 
| 2 | No | 559 | 
                                    
                                    54.6%
                                 |