| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 3 | 
                                                                 
                                    
                                    0.8%
                                 
                                                             | 
                                                        
                    
| 2 | 4 | 
                                                                 
                                    
                                    1.1%
                                 
                                                             | 
                                                        
                    |
| 3 | 24 | 
                                                                 
                                    
                                    6.8%
                                 
                                                             | 
                                                        
                    |
| 4 | 23 | 
                                                                 
                                    
                                    6.5%
                                 
                                                             | 
                                                        
                    |
| 5 | 59 | 
                                                                 
                                    
                                    16.7%
                                 
                                                             | 
                                                        
                    |
| 6 | 61 | 
                                                                 
                                    
                                    17.3%
                                 
                                                             | 
                                                        
                    |
| 7 | 61 | 
                                                                 
                                    
                                    17.3%
                                 
                                                             | 
                                                        
                    |
| 8 | 54 | 
                                                                 
                                    
                                    15.3%
                                 
                                                             | 
                                                        
                    |
| 9 | 35 | 
                                                                 
                                    
                                    9.9%
                                 
                                                             | 
                                                        
                    |
| 10 | Very effective | 29 | 
                                                                 
                                    
                                    8.2%
                                 
                                                             | 
                                                        
                    
| -99 | 54 | ||
| 11 | Don't know | 102 | |
| Sysmiss | 148 |