| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 1 | 
                                                                 
                                    
                                    0.8%
                                 
                                                             | 
                                                        
                    
| 2 | 4 | 
                                                                 
                                    
                                    3.3%
                                 
                                                             | 
                                                        
                    |
| 3 | 2 | 
                                                                 
                                    
                                    1.7%
                                 
                                                             | 
                                                        
                    |
| 4 | 4 | 
                                                                 
                                    
                                    3.3%
                                 
                                                             | 
                                                        
                    |
| 5 | 8 | 
                                                                 
                                    
                                    6.6%
                                 
                                                             | 
                                                        
                    |
| 6 | 8 | 
                                                                 
                                    
                                    6.6%
                                 
                                                             | 
                                                        
                    |
| 7 | 39 | 
                                                                 
                                    
                                    32.2%
                                 
                                                             | 
                                                        
                    |
| 8 | 29 | 
                                                                 
                                    
                                    24%
                                 
                                                             | 
                                                        
                    |
| 9 | 22 | 
                                                                 
                                    
                                    18.2%
                                 
                                                             | 
                                                        
                    |
| 10 | Extremely effective | 4 | 
                                                                 
                                    
                                    3.3%
                                 
                                                             | 
                                                        
                    
| 11 | Don't know | 13 | |
| Sysmiss | 4 |