| Value | 
                    Category | 
                                                                            
                                    
                    
                        | 0 | 
                        Not given  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 4 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 6 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 7 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 8 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 9 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 10 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 11 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 12 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 44 | 
                        Marked on card  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 97 | 
                        Inconsistent  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 98 | 
                        DK  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 99 | 
                        Missing  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | Sysmiss | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                            
            Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.