| Value | Category | 
                                    
                    
                        | 0 |  | 
                                    
                    
                        | 1 | no difficulties | 
                                    
                    
                        | 2 | high price | 
                                    
                    
                        | 3 | not available | 
                                    
                    
                        | 4 | too far to get | 
                                    
                    
                        | 5 | other | 
                                    
                    
                        | 6 | donot need to use | 
                            
            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.