| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 | 
                                    
                                    1%
                                 | 
| 1 | Yes | 548 | 
                                    
                                    89.5%
                                 | 
| 2 | No | 58 | 
                                    
                                    9.5%
                                 |