| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 | 
                                    
                                    1%
                                 | 
| 1 | Yes | 31 | 
                                    
                                    5.2%
                                 | 
| 2 | No | 563 | 
                                    
                                    93.8%
                                 |