| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 | 
                                    
                                    0.1%
                                 | 
| -7 | Does not apply (sponatneous) | 29 | 
                                    
                                    2.8%
                                 | 
| 1 | Yes | 193 | 
                                    
                                    18.8%
                                 | 
| 2 | No | 801 | 
                                    
                                    78.2%
                                 |