| Value | 
                    Category | 
                                                                            
                                    
                    
                        | -5 | 
                        other  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | -4 | 
                        missing  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | -3 | 
                        refused to answer  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | -2 | 
                        not applicable  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | -1 | 
                        do not know  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 1200 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 1500 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 2000 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 6000 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 7000 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 10000 | 
                          | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 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.