| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 11 | 
                                    
                                    13.9%
                                 | 
| 0 | 24 | 
                                    
                                    30.4%
                                 | |
| 10 | 2 | 
                                    
                                    2.5%
                                 | |
| 18 | 1 | 
                                    
                                    1.3%
                                 | |
| 20 | 2 | 
                                    
                                    2.5%
                                 | |
| 25 | 1 | 
                                    
                                    1.3%
                                 | |
| 40 | 3 | 
                                    
                                    3.8%
                                 | |
| 50 | 4 | 
                                    
                                    5.1%
                                 | |
| 60 | 3 | 
                                    
                                    3.8%
                                 | |
| 65 | 1 | 
                                    
                                    1.3%
                                 | |
| 70 | 4 | 
                                    
                                    5.1%
                                 | |
| 80 | 4 | 
                                    
                                    5.1%
                                 | |
| 90 | 3 | 
                                    
                                    3.8%
                                 | |
| 92 | 1 | 
                                    
                                    1.3%
                                 | |
| 99 | 1 | 
                                    
                                    1.3%
                                 | |
| 100 | 14 | 
                                    
                                    17.7%
                                 | |
| Sysmiss | 32 |