| Value | Category | Cases | |
|---|---|---|---|
| 2015 | 8 | 
                                    
                                    0.2%
                                 | |
| 2016 | 297 | 
                                    
                                    7.9%
                                 | |
| 2017 | 623 | 
                                    
                                    16.6%
                                 | |
| 2018 | 201 | 
                                    
                                    5.4%
                                 | |
| 9999 | NO RESPONDE | 1 | 
                                    
                                    0%
                                 | 
| Sysmiss | 2627 | 
                                    
                                    69.9%
                                 |