| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 | 
                                    
                                    0%
                                 | 
| 1 | Yes | 44 | 
                                    
                                    12.1%
                                 | 
| 2 | No | 320 | 
                                    
                                    87.9%
                                 |