| Value | Category | Cases | |
|---|---|---|---|
| 0 | 18 | 
                                    
                                    0.2%
                                 | |
| 1 | 6 | 
                                    
                                    0.1%
                                 | |
| Missing value | 8221 | 
                                    
                                    99.7%
                                 |