| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 28 | 
                                    
                                    2.9%
                                 | 
| 1 | Yes | 502 | 
                                    
                                    52.6%
                                 | 
| 2 | No | 425 | 
                                    
                                    44.5%
                                 |