| Value | Category | Cases | |
|---|---|---|---|
| a | 135 | 
                                    
                                    67.5%
                                 | |
| ab | 31 | 
                                    
                                    15.5%
                                 | |
| abd | 1 | 
                                    
                                    0.5%
                                 | |
| ad | 4 | 
                                    
                                    2%
                                 | |
| b | 21 | 
                                    
                                    10.5%
                                 | |
| c | 2 | 
                                    
                                    1%
                                 | |
| d | 6 | 
                                    
                                    3%
                                 |