| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 10 | 
                                    
                                    4.7%
                                 | 
| 0 | 195 | 
                                    
                                    90.7%
                                 | |
| 5 | 2 | 
                                    
                                    0.9%
                                 | |
| 15 | 1 | 
                                    
                                    0.5%
                                 | |
| 18 | 1 | 
                                    
                                    0.5%
                                 | |
| 20 | 1 | 
                                    
                                    0.5%
                                 | |
| 25 | 1 | 
                                    
                                    0.5%
                                 | |
| 50 | 1 | 
                                    
                                    0.5%
                                 | |
| 60 | 1 | 
                                    
                                    0.5%
                                 | |
| 70 | 1 | 
                                    
                                    0.5%
                                 | |
| 100 | 1 | 
                                    
                                    0.5%
                                 |