| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 | 
                                    
                                    0.6%
                                 | 
| 4 | 1 | 
                                    
                                    0.3%
                                 | |
| 15 | 1 | 
                                    
                                    0.3%
                                 | |
| 20 | 1 | 
                                    
                                    0.3%
                                 | |
| 25 | 1 | 
                                    
                                    0.3%
                                 | |
| 30 | 3 | 
                                    
                                    0.8%
                                 | |
| 40 | 5 | 
                                    
                                    1.4%
                                 | |
| 50 | 21 | 
                                    
                                    5.8%
                                 | |
| 60 | 48 | 
                                    
                                    13.2%
                                 | |
| 65 | 2 | 
                                    
                                    0.6%
                                 | |
| 70 | 70 | 
                                    
                                    19.3%
                                 | |
| 75 | 3 | 
                                    
                                    0.8%
                                 | |
| 80 | 43 | 
                                    
                                    11.8%
                                 | |
| 81 | 1 | 
                                    
                                    0.3%
                                 | |
| 85 | 3 | 
                                    
                                    0.8%
                                 | |
| 90 | 20 | 
                                    
                                    5.5%
                                 | |
| 95 | 8 | 
                                    
                                    2.2%
                                 | |
| 98 | 1 | 
                                    
                                    0.3%
                                 | |
| 99 | 1 | 
                                    
                                    0.3%
                                 | |
| 100 | 128 | 
                                    
                                    35.3%
                                 |