| Value | Category | Cases | |
|---|---|---|---|
| 1995 | 7 | 
                                                                 
                                    
                                    2.1%
                                 
                                                             | 
                                                        
                    |
| 1996 | 120 | 
                                                                 
                                    
                                    36.7%
                                 
                                                             | 
                                                        
                    |
| 1997 | 106 | 
                                                                 
                                    
                                    32.4%
                                 
                                                             | 
                                                        
                    |
| 1998 | 66 | 
                                                                 
                                    
                                    20.2%
                                 
                                                             | 
                                                        
                    |
| 1999 | 18 | 
                                                                 
                                    
                                    5.5%
                                 
                                                             | 
                                                        
                    |
| 2000 | 10 | 
                                                                 
                                    
                                    3.1%
                                 
                                                             | 
                                                        
                    |
| 9997 | inconsistent | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| 9998 | dk | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 6428 |