| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 4 | 
                                    
                                    5.1%
                                 | |
| 2005 | 1 | 
                                    
                                    1.3%
                                 | |
| 2006 | 6 | 
                                    
                                    7.7%
                                 | |
| 2007 | 7 | 
                                    
                                    9%
                                 | |
| 2008 | 10 | 
                                    
                                    12.8%
                                 | |
| 2009 | 10 | 
                                    
                                    12.8%
                                 | |
| 2010 | 16 | 
                                    
                                    20.5%
                                 | |
| 2011 | 12 | 
                                    
                                    15.4%
                                 | |
| 2012 | 5 | 
                                    
                                    6.4%
                                 | |
| 2013 | 7 | 
                                    
                                    9%
                                 | |
| Sysmiss | 173 |