| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 1 | 
                                                                 
                                    
                                    0.7%
                                 
                                                             | 
                                                        
                    
| 2 | 3 | 
                                                                 
                                    
                                    2%
                                 
                                                             | 
                                                        
                    |
| 3 | 6 | 
                                                                 
                                    
                                    4.1%
                                 
                                                             | 
                                                        
                    |
| 4 | 13 | 
                                                                 
                                    
                                    8.8%
                                 
                                                             | 
                                                        
                    |
| 5 | 18 | 
                                                                 
                                    
                                    12.2%
                                 
                                                             | 
                                                        
                    |
| 6 | 16 | 
                                                                 
                                    
                                    10.9%
                                 
                                                             | 
                                                        
                    |
| 7 | 29 | 
                                                                 
                                    
                                    19.7%
                                 
                                                             | 
                                                        
                    |
| 8 | 28 | 
                                                                 
                                    
                                    19%
                                 
                                                             | 
                                                        
                    |
| 9 | 28 | 
                                                                 
                                    
                                    19%
                                 
                                                             | 
                                                        
                    |
| 10 | Very effective | 5 | 
                                                                 
                                    
                                    3.4%
                                 
                                                             | 
                                                        
                    
| 11 | Don't know | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 228 |