| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 | 
                                    
                                    1%
                                 | 
| 1 | 5 | 
                                    
                                    4.9%
                                 | |
| 2 | 28 | 
                                    
                                    27.5%
                                 | |
| 3 | 11 | 
                                    
                                    10.8%
                                 | |
| 4 | 11 | 
                                    
                                    10.8%
                                 | |
| 5 | 3 | 
                                    
                                    2.9%
                                 | |
| 6 | 7 | 
                                    
                                    6.9%
                                 | |
| 8 | 6 | 
                                    
                                    5.9%
                                 | |
| 9 | 1 | 
                                    
                                    1%
                                 | |
| 10 | 1 | 
                                    
                                    1%
                                 | |
| 12 | 19 | 
                                    
                                    18.6%
                                 | |
| 13 | 1 | 
                                    
                                    1%
                                 | |
| 15 | 2 | 
                                    
                                    2%
                                 | |
| 20 | 1 | 
                                    
                                    1%
                                 | |
| 25 | 1 | 
                                    
                                    1%
                                 | |
| 36 | 1 | 
                                    
                                    1%
                                 | |
| 48 | 2 | 
                                    
                                    2%
                                 | |
| 84 | 1 | 
                                    
                                    1%
                                 | |
| Sysmiss | 55 |