| Value | Category | Cases | |
|---|---|---|---|
| 88 | Don't know | 0 | 
                                    
                                    0%
                                 | 
| 99 | Missing | 2 | 
                                    
                                    0.2%
                                 | 
| 2012 | 994 | 
                                    
                                    99.2%
                                 | |
| 2013 | 6 | 
                                    
                                    0.6%
                                 |