| Value | Category | Cases | |
|---|---|---|---|
| 1996 | 80 | 
                                                                 
                                    
                                    24.3%
                                 
                                                             | 
                                                        
                    |
| 1997 | 116 | 
                                                                 
                                    
                                    35.3%
                                 
                                                             | 
                                                        
                    |
| 1998 | 83 | 
                                                                 
                                    
                                    25.2%
                                 
                                                             | 
                                                        
                    |
| 1999 | 37 | 
                                                                 
                                    
                                    11.2%
                                 
                                                             | 
                                                        
                    |
| 2000 | 13 | 
                                                                 
                                    
                                    4%
                                 
                                                             | 
                                                        
                    |
| 9997 | inconsistent | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| 9998 | dk | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 6426 |