| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 10 | 
                                    
                                    0.7%
                                 | 
| 1 | Yes | 130 | 
                                    
                                    9.2%
                                 | 
| 2 | No | 1276 | 
                                    
                                    90.1%
                                 |