| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 1 | 
                                                                 
                                    
                                    0.7%
                                 
                                                             | 
                                                        
                    
| 2 | 2 | 3 | 
                                                                 
                                    
                                    2.2%
                                 
                                                             | 
                                                        
                    
| 3 | 3 | 4 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    
| 4 | 4 | 8 | 
                                                                 
                                    
                                    6%
                                 
                                                             | 
                                                        
                    
| 5 | 5 | 15 | 
                                                                 
                                    
                                    11.2%
                                 
                                                             | 
                                                        
                    
| 6 | 6 | 11 | 
                                                                 
                                    
                                    8.2%
                                 
                                                             | 
                                                        
                    
| 7 | 7 | 20 | 
                                                                 
                                    
                                    14.9%
                                 
                                                             | 
                                                        
                    
| 8 | 8 | 20 | 
                                                                 
                                    
                                    14.9%
                                 
                                                             | 
                                                        
                    
| 9 | 9 | 7 | 
                                                                 
                                    
                                    5.2%
                                 
                                                             | 
                                                        
                    
| 10 | Very effective | 10 | 
                                                                 
                                    
                                    7.5%
                                 
                                                             | 
                                                        
                    
| 11 | Don't know | 35 | 
                                                                 
                                    
                                    26.1%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 12 |