| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 | 
                                    
                                    0.9%
                                 | 
| 0 | 210 | 
                                    
                                    97.7%
                                 | |
| 3 | 1 | 
                                    
                                    0.5%
                                 | |
| 10 | 1 | 
                                    
                                    0.5%
                                 | |
| 11 | 1 | 
                                    
                                    0.5%
                                 |