| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 33 | 
                                    
                                    10.3%
                                 | 
| 0 | 23 | 
                                    
                                    7.2%
                                 | |
| 1 | 86 | 
                                    
                                    27%
                                 | |
| 2 | 28 | 
                                    
                                    8.8%
                                 | |
| 3 | 11 | 
                                    
                                    3.4%
                                 | |
| 4 | 5 | 
                                    
                                    1.6%
                                 | |
| 5 | 29 | 
                                    
                                    9.1%
                                 | |
| 7 | 1 | 
                                    
                                    0.3%
                                 | |
| 8 | 1 | 
                                    
                                    0.3%
                                 | |
| 10 | 40 | 
                                    
                                    12.5%
                                 | |
| 15 | 7 | 
                                    
                                    2.2%
                                 | |
| 20 | 19 | 
                                    
                                    6%
                                 | |
| 25 | 6 | 
                                    
                                    1.9%
                                 | |
| 30 | 10 | 
                                    
                                    3.1%
                                 | |
| 35 | 1 | 
                                    
                                    0.3%
                                 | |
| 40 | 3 | 
                                    
                                    0.9%
                                 | |
| 50 | 6 | 
                                    
                                    1.9%
                                 | |
| 60 | 1 | 
                                    
                                    0.3%
                                 | |
| 80 | 1 | 
                                    
                                    0.3%
                                 | |
| 100 | 8 | 
                                    
                                    2.5%
                                 | |
| Sysmiss | 1097 |