| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 | 
                                    
                                    0%
                                 | 
| 1 | Yes | 55 | 
                                    
                                    9%
                                 | 
| 2 | No | 557 | 
                                    
                                    91%
                                 |