| Value | Category | Cases | |
|---|---|---|---|
| 1994 | 6 | 
                                                                 
                                    
                                    2.3%
                                 
                                                             | 
                                                        
                    |
| 1995 | 3 | 
                                                                 
                                    
                                    1.1%
                                 
                                                             | 
                                                        
                    |
| 1996 | 6 | 
                                                                 
                                    
                                    2.3%
                                 
                                                             | 
                                                        
                    |
| 1997 | 14 | 
                                                                 
                                    
                                    5.3%
                                 
                                                             | 
                                                        
                    |
| 1998 | 70 | 
                                                                 
                                    
                                    26.3%
                                 
                                                             | 
                                                        
                    |
| 1999 | 94 | 
                                                                 
                                    
                                    35.3%
                                 
                                                             | 
                                                        
                    |
| 2000 | 73 | 
                                                                 
                                    
                                    27.4%
                                 
                                                             | 
                                                        
                    |
| 9997 | inconsistent | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| 9998 | dk | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 15719 |