| Value | Category | Cases | |
|---|---|---|---|
| 2005 | 33 | 
                                                                 
                                    
                                    1.1%
                                 
                                                             | 
                                                        
                    |
| 2006 | 270 | 
                                                                 
                                    
                                    9%
                                 
                                                             | 
                                                        
                    |
| 2007 | 443 | 
                                                                 
                                    
                                    14.7%
                                 
                                                             | 
                                                        
                    |
| 2008 | 664 | 
                                                                 
                                    
                                    22.1%
                                 
                                                             | 
                                                        
                    |
| 2009 | 887 | 
                                                                 
                                    
                                    29.5%
                                 
                                                             | 
                                                        
                    |
| 2010 | 704 | 
                                                                 
                                    
                                    23.4%
                                 
                                                             | 
                                                        
                    |
| 9997 | inconsistent | 9 | 
                                                                 
                                    
                                    0.3%
                                 
                                                             | 
                                                        
                    
| 9998 | dk | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| 10001 | .Z | 15744 |