| Value | Category | Cases | |
|---|---|---|---|
| 1 | high quality | 750 | 
                                                                 
                                    
                                    9.5%
                                 
                                                             | 
                                                        
                    
| 2 | good | 2712 | 
                                                                 
                                    
                                    34.5%
                                 
                                                             | 
                                                        
                    
| 3 | satisfactory | 3495 | 
                                                                 
                                    
                                    44.4%
                                 
                                                             | 
                                                        
                    
| 4 | bad | 754 | 
                                                                 
                                    
                                    9.6%
                                 
                                                             | 
                                                        
                    
| 5 | very bad | 161 | 
                                                                 
                                    
                                    2%
                                 
                                                             |