| Value | Category | 
                                    
                    
                        | 1 | One year or less | 
                                    
                    
                        | 2 | Under 2 years | 
                                    
                    
                        | 3 | 2 to 5 years | 
                                    
                    
                        | 4 | 6 to 10 years | 
                                    
                    
                        | 5 | More than 10 years | 
                                    
                    
                        | 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.