| Value | Category | Cases | |
|---|---|---|---|
| 1996 | 10 | 
                                                                 
                                    
                                    35.7%
                                 
                                                             | 
                                                        
                    |
| 1997 | 15 | 
                                                                 
                                    
                                    53.6%
                                 
                                                             | 
                                                        
                    |
| 1998 | 1 | 
                                                                 
                                    
                                    3.6%
                                 
                                                             | 
                                                        
                    |
| 2000 | 2 | 
                                                                 
                                    
                                    7.1%
                                 
                                                             | 
                                                        
                    |
| 9997 | inconsistent | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| 9998 | dk | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 6727 |