| Value | Category | Cases | |
|---|---|---|---|
| 1 | Not effective at all | 4 | 
                                    
                                    0.7%
                                 | 
| 2 | 8 | 
                                    
                                    1.3%
                                 | |
| 3 | 11 | 
                                    
                                    1.8%
                                 | |
| 4 | 35 | 
                                    
                                    5.7%
                                 | |
| 5 | 79 | 
                                    
                                    13%
                                 | |
| 6 | 94 | 
                                    
                                    15.4%
                                 | |
| 7 | 109 | 
                                    
                                    17.9%
                                 | |
| 8 | 84 | 
                                    
                                    13.8%
                                 | |
| 9 | 54 | 
                                    
                                    8.9%
                                 | |
| 10 | Very effective | 45 | 
                                    
                                    7.4%
                                 | 
| 11 | Don't know | 87 | 
                                    
                                    14.3%
                                 | 
| Sysmiss | 14 |