| Value | Category | Cases | |
|---|---|---|---|
| 1 | No difficulty | 4825 | 
                                                                 
                                    
                                    58.5%
                                 
                                                             | 
                                                        
                    
| 2 | Minor difficult | 723 | 
                                                                 
                                    
                                    8.8%
                                 
                                                             | 
                                                        
                    
| 3 | Big difficulty | 1655 | 
                                                                 
                                    
                                    20.1%
                                 
                                                             | 
                                                        
                    
| 8 | NA | 1013 | |
| 9 | I don’t know | 11 | |
| Sysmiss | 17 |