| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 15 | 
                                    
                                    18.5%
                                 | 
| 0 | 4 | 
                                    
                                    4.9%
                                 | |
| 1 | 25 | 
                                    
                                    30.9%
                                 | |
| 2 | 12 | 
                                    
                                    14.8%
                                 | |
| 3 | 10 | 
                                    
                                    12.3%
                                 | |
| 4 | 7 | 
                                    
                                    8.6%
                                 | |
| 5 | 3 | 
                                    
                                    3.7%
                                 | |
| 6 | 2 | 
                                    
                                    2.5%
                                 | |
| 8 | 1 | 
                                    
                                    1.2%
                                 | |
| 50 | 1 | 
                                    
                                    1.2%
                                 | |
| 60 | 1 | 
                                    
                                    1.2%
                                 | |
| Sysmiss | 30 |