| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 261 | 
                                                                 
                                    
                                    16.4%
                                 
                                                             | 
                                                        
                    
| 0 | 454 | 
                                                                 
                                    
                                    28.4%
                                 
                                                             | 
                                                        
                    |
| 1 | 616 | 
                                                                 
                                    
                                    38.6%
                                 
                                                             | 
                                                        
                    |
| 2 | 131 | 
                                                                 
                                    
                                    8.2%
                                 
                                                             | 
                                                        
                    |
| 3 | 44 | 
                                                                 
                                    
                                    2.8%
                                 
                                                             | 
                                                        
                    |
| 4 | 9 | 
                                                                 
                                    
                                    0.6%
                                 
                                                             | 
                                                        
                    |
| 5 | 22 | 
                                                                 
                                    
                                    1.4%
                                 
                                                             | 
                                                        
                    |
| 6 | 2 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 7 | 6 | 
                                                                 
                                    
                                    0.4%
                                 
                                                             | 
                                                        
                    |
| 10 | 20 | 
                                                                 
                                    
                                    1.3%
                                 
                                                             | 
                                                        
                    |
| 12 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 15 | 5 | 
                                                                 
                                    
                                    0.3%
                                 
                                                             | 
                                                        
                    |
| 17 | 2 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 20 | 4 | 
                                                                 
                                    
                                    0.3%
                                 
                                                             | 
                                                        
                    |
| 21 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 22 | 2 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 30 | 10 | 
                                                                 
                                    
                                    0.6%
                                 
                                                             | 
                                                        
                    |
| 40 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 50 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 90 | 1 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 100 | 3 | 
                                                                 
                                    
                                    0.2%
                                 
                                                             | 
                                                        
                    |
| Sysmiss | 129 |