| Value | Category | 
                                    
                    
                        | 1 | iron sheets | 
                                    
                    
                        | 2 | thatch/grass | 
                                    
                    
                        | 3 | earth tiles | 
                                    
                    
                        | 4 | industrial tiles | 
                                    
                    
                        | 5 | wood | 
                                    
                    
                        | 6 | cement/concrete | 
                                    
                    
                        | 7 | carton | 
                                    
                    
                        | 8 | other | 
                                    
                    
                        | 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.