| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 | 
                                    
                                    0%
                                 | 
| 1 | 128 | 
                                    
                                    39.1%
                                 | |
| 2 | 94 | 
                                    
                                    28.7%
                                 | |
| 3 | 33 | 
                                    
                                    10.1%
                                 | |
| 4 | 12 | 
                                    
                                    3.7%
                                 | |
| 5 | 13 | 
                                    
                                    4%
                                 | |
| 6 | 7 | 
                                    
                                    2.1%
                                 | |
| 7 | 3 | 
                                    
                                    0.9%
                                 | |
| 10 | 6 | 
                                    
                                    1.8%
                                 | |
| 11 | 1 | 
                                    
                                    0.3%
                                 | |
| 12 | 17 | 
                                    
                                    5.2%
                                 | |
| 13 | 6 | 
                                    
                                    1.8%
                                 | |
| 15 | 1 | 
                                    
                                    0.3%
                                 | |
| 17 | 1 | 
                                    
                                    0.3%
                                 | |
| 20 | 4 | 
                                    
                                    1.2%
                                 | |
| 30 | 1 | 
                                    
                                    0.3%
                                 | |
| Sysmiss | 36 |