| Value | Category | Cases | |
|---|---|---|---|
| 0 | no | 2017 | 
                                                                 
                                    
                                    70.2%
                                 
                                                             | 
                                                        
                    
| 1 | gave but don't know times | 538 | 
                                                                 
                                    
                                    18.7%
                                 
                                                             | 
                                                        
                    
| 8 | don't know | 317 | 
                                                                 
                                    
                                    11%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 3883 |