| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2459 | 
                                                                 
                                    
                                    23%
                                 
                                                             | 
                                                        
                    
| 0 | 201 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1 | 5900 | 
                                                                 
                                    
                                    55.3%
                                 
                                                             | 
                                                        
                    |
| 2 | 1630 | 
                                                                 
                                    
                                    15.3%
                                 
                                                             | 
                                                        
                    |
| 3 | 300 | 
                                                                 
                                    
                                    2.8%
                                 
                                                             | 
                                                        
                    |
| 4 | 118 | 
                                                                 
                                    
                                    1.1%
                                 
                                                             | 
                                                        
                    |
| 5 | 37 | 
                                                                 
                                    
                                    0.3%
                                 
                                                             | 
                                                        
                    |
| 6 | 11 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 7 | 3 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 8 | 7 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 9 | 1 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 10 | 2 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 12 | 1 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 15 | 2 | 
                                                                 
                                    
                                    0%
                                 
                                                             |