| Value | Category | Cases | |
|---|---|---|---|
| 1995 | 1 | 
                                    
                                    0.2%
                                 | |
| 1996 | 2 | 
                                    
                                    0.3%
                                 | |
| 1997 | 34 | 
                                    
                                    5.5%
                                 | |
| 1998 | 38 | 
                                    
                                    6.1%
                                 | |
| 1999 | 68 | 
                                    
                                    10.9%
                                 | |
| 2000 | 96 | 
                                    
                                    15.4%
                                 | |
| 2001 | 222 | 
                                    
                                    35.7%
                                 | |
| 2002 | 161 | 
                                    
                                    25.9%
                                 | |
| Sysmiss | 7427 |