| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not useful | 1 | 
                                                                 
                                    
                                    1.2%
                                 
                                                             | 
                                                        
                    
| 2 | Fairly useful | 19 | 
                                                                 
                                    
                                    23.5%
                                 
                                                             | 
                                                        
                    
| 3 | Useful | 48 | 
                                                                 
                                    
                                    59.3%
                                 
                                                             | 
                                                        
                    
| 4 | Very useful | 13 | 
                                                                 
                                    
                                    16%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 510 |