| Value | Category | Cases | |
|---|---|---|---|
| 2009 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 2010 | 2 | 
                                                                 
                                    
                                    1%
                                 
                                                             | 
                                                        
                    |
| 2011 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 2012 | 4 | 
                                                                 
                                    
                                    2.1%
                                 
                                                             | 
                                                        
                    |
| 2013 | 25 | 
                                                                 
                                    
                                    12.8%
                                 
                                                             | 
                                                        
                    |
| 2014 | 31 | 
                                                                 
                                    
                                    15.9%
                                 
                                                             | 
                                                        
                    |
| 2015 | 95 | 
                                                                 
                                    
                                    48.7%
                                 
                                                             | 
                                                        
                    |
| 2016 | 34 | 
                                                                 
                                    
                                    17.4%
                                 
                                                             | 
                                                        
                    |
| Sysmiss | 144 |