| Value | Category | Cases | |
|---|---|---|---|
| 1998 | 60 | 
                                                                 
                                    
                                    74.1%
                                 
                                                             | 
                                                        
                    |
| 1999 | 21 | 
                                                                 
                                    
                                    25.9%
                                 
                                                             | 
                                                        
                    |
| Sysmiss | 190 |