| Value | Category | 
                                    
                    
                        | 0 | do not answer the question | 
                                    
                    
                        | 1 | 0-5 years | 
                                    
                    
                        | 2 | 6-10 | 
                                    
                    
                        | 3 | 11-15 | 
                                    
                    
                        | 4 | 16-20 | 
                                    
                    
                        | 5 | 21-25 | 
                                    
                    
                        | 6 | 26-30 | 
                                    
                    
                        | 7 | 31-35 | 
                                    
                    
                        | 8 | 36-40 | 
                                    
                    
                        | 9 | 41 years or more | 
                                    
                    
                        | 99 | there is no data | 
                            
            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.