| Value | Category | Cases | |
|---|---|---|---|
| 2000 | 3 | 
                                    
                                    3.4%
                                 | |
| 2002 | 6 | 
                                    
                                    6.8%
                                 | |
| 2003 | 25 | 
                                    
                                    28.4%
                                 | |
| 2004 | 54 | 
                                    
                                    61.4%
                                 | |
| Sysmiss | 279 |