| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 1 | 
                                    
                                    0.8%
                                 | 
| 2 | 5 | 
                                    
                                    3.8%
                                 | |
| 3 | 7 | 
                                    
                                    5.3%
                                 | |
| 4 | 5 | 
                                    
                                    3.8%
                                 | |
| 5 | 19 | 
                                    
                                    14.3%
                                 | |
| 6 | 14 | 
                                    
                                    10.5%
                                 | |
| 7 | 23 | 
                                    
                                    17.3%
                                 | |
| 8 | 19 | 
                                    
                                    14.3%
                                 | |
| 9 | 12 | 
                                    
                                    9%
                                 | |
| 10 | Very effective | 7 | 
                                    
                                    5.3%
                                 | 
| 11 | Don't know | 21 | 
                                    
                                    15.8%
                                 | 
| Sysmiss | 1 |