| Value | Category | Cases | |
|---|---|---|---|
| 1 | No difficulty | 5829 | 
                                                                 
                                    
                                    70.7%
                                 
                                                             | 
                                                        
                    
| 2 | Minor difficult | 818 | 
                                                                 
                                    
                                    9.9%
                                 
                                                             | 
                                                        
                    
| 3 | Big difficulty | 1472 | 
                                                                 
                                    
                                    17.9%
                                 
                                                             | 
                                                        
                    
| 8 | NA | 104 | |
| 9 | I don’t know | 4 | |
| Sysmiss | 17 |