| Value | Category | Cases | |
|---|---|---|---|
| -99 | 6 | 
                                    
                                    1.6%
                                 | |
| 1 | Not effective at all | 3 | 
                                    
                                    0.8%
                                 | 
| 2 | 1 | 
                                    
                                    0.3%
                                 | |
| 3 | 3 | 
                                    
                                    0.8%
                                 | |
| 4 | 4 | 
                                    
                                    1%
                                 | |
| 5 | 17 | 
                                    
                                    4.5%
                                 | |
| 6 | 35 | 
                                    
                                    9.2%
                                 | |
| 7 | 47 | 
                                    
                                    12.3%
                                 | |
| 8 | 42 | 
                                    
                                    11%
                                 | |
| 9 | 29 | 
                                    
                                    7.6%
                                 | |
| 10 | Very effective | 11 | 
                                    
                                    2.9%
                                 | 
| 11 | Don't know | 184 | 
                                    
                                    48.2%
                                 | 
| Sysmiss | 47 |