| Value | 
                    Category | 
                                                                            
                                    
                    
                        | -9 | 
                        Don't know  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | -8 | 
                        Refused  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 10 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 15 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 20 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 25 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 30 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 36 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 40 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 48 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 50 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 55 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 60 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 65 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 68 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 70 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 75 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 80 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 82 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 83 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 85 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 88 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 90 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 95 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 96 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 99 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 100 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                            
            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.