| Value | Category | Cases | |
|---|---|---|---|
| -99 | 3 | 
                                    
                                    0.8%
                                 | |
| 1 | Not effective at all | 4 | 
                                    
                                    1%
                                 | 
| 2 | 4 | 
                                    
                                    1%
                                 | |
| 3 | 3 | 
                                    
                                    0.8%
                                 | |
| 4 | 5 | 
                                    
                                    1.3%
                                 | |
| 5 | 27 | 
                                    
                                    7.1%
                                 | |
| 6 | 28 | 
                                    
                                    7.3%
                                 | |
| 7 | 62 | 
                                    
                                    16.2%
                                 | |
| 8 | 76 | 
                                    
                                    19.9%
                                 | |
| 9 | 39 | 
                                    
                                    10.2%
                                 | |
| 10 | Very effective | 17 | 
                                    
                                    4.5%
                                 | 
| 11 | Don't know | 114 | 
                                    
                                    29.8%
                                 | 
| Sysmiss | 47 |