| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 399 | 
                                                                 
                                    
                                    26.4%
                                 
                                                             | 
                                                        
                    
| 0 | 1031 | 
                                                                 
                                    
                                    68.2%
                                 
                                                             | 
                                                        
                    |
| 1 | 21 | 
                                                                 
                                    
                                    1.4%
                                 
                                                             | 
                                                        
                    |
| 2 | 10 | 
                                                                 
                                    
                                    0.7%
                                 
                                                             | 
                                                        
                    |
| 3 | 6 | 
                                                                 
                                    
                                    0.4%
                                 
                                                             | 
                                                        
                    |
| 4 | 6 | 
                                                                 
                                    
                                    0.4%
                                 
                                                             | 
                                                        
                    |
| 5 | 9 | 
                                                                 
                                    
                                    0.6%
                                 
                                                             | 
                                                        
                    |
| 6 | 6 | 
                                                                 
                                    
                                    0.4%
                                 
                                                             | 
                                                        
                    |
| 7 | 2 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 8 | 2 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 10 | 17 | 
                                                                 
                                    
                                    1.1%
                                 
                                                             | 
                                                        
                    |
| 11 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 15 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 30 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| Sysmiss | 1443 |