| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 22 | 
                                    
                                    2.3%
                                 | 
| 1 | Yes | 408 | 
                                    
                                    42.7%
                                 | 
| 2 | No | 525 | 
                                    
                                    55%
                                 |