| Value | Category | 
                                    
                    
                        | ? |  | 
                                    
                    
                        | ??? |  | 
                                    
                    
                        | AND IT WAS GIVEN AS HOUSEHOLD USAGE. THEREFOR, REQUIRED TO TRANSFER IT TO CLASSIFICATION OF NC |  | 
                            
            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.