| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 4022 | 
                                                                 
                                    
                                    37.7%
                                 
                                                             | 
                                                        
                    
| 0 | 1626 | 
                                                                 
                                    
                                    15.2%
                                 
                                                             | 
                                                        
                    |
| 1 | 3900 | 
                                                                 
                                    
                                    36.6%
                                 
                                                             | 
                                                        
                    |
| 2 | 991 | 
                                                                 
                                    
                                    9.3%
                                 
                                                             | 
                                                        
                    |
| 3 | 82 | 
                                                                 
                                    
                                    0.8%
                                 
                                                             | 
                                                        
                    |
| 4 | 33 | 
                                                                 
                                    
                                    0.3%
                                 
                                                             | 
                                                        
                    |
| 5 | 5 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 6 | 3 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 7 | 1 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 8 | 4 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| Sysmiss | 5 |