| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 | 
                                    
                                    0.9%
                                 | 
| 1 | Yes | 206 | 
                                    
                                    31.9%
                                 | 
| 2 | No | 433 | 
                                    
                                    67.1%
                                 |