| Value | Category | Cases | |
|---|---|---|---|
| 2015 | 4 | 
                                    
                                    0.3%
                                 | |
| 2016 | 234 | 
                                    
                                    15%
                                 | |
| 2017 | 277 | 
                                    
                                    17.7%
                                 | |
| 2018 | 237 | 
                                    
                                    15.2%
                                 | |
| 2019 | 9 | 
                                    
                                    0.6%
                                 | |
| 9999 | NO RESPONSE | 2 | 
                                    
                                    0.1%
                                 | 
| Sysmiss | 801 | 
                                    
                                    51.2%
                                 |