| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 | 
                                    
                                    1%
                                 | 
| 0 | 9 | 
                                    
                                    2.9%
                                 | |
| 10 | 1 | 
                                    
                                    0.3%
                                 | |
| 20 | 5 | 
                                    
                                    1.6%
                                 | |
| 30 | 5 | 
                                    
                                    1.6%
                                 | |
| 50 | 14 | 
                                    
                                    4.5%
                                 | |
| 60 | 2 | 
                                    
                                    0.6%
                                 | |
| 70 | 3 | 
                                    
                                    1%
                                 | |
| 80 | 8 | 
                                    
                                    2.6%
                                 | |
| 85 | 1 | 
                                    
                                    0.3%
                                 | |
| 90 | 4 | 
                                    
                                    1.3%
                                 | |
| 95 | 3 | 
                                    
                                    1%
                                 | |
| 100 | 253 | 
                                    
                                    81.4%
                                 |