| Value | Category | 
                                    
                    
                        | 1 | Public transport | 
                                    
                    
                        | 2 | Walk | 
                                    
                    
                        | 3 | Private vehicle | 
                                    
                    
                        | 4 | School bus | 
                                    
                    
                        | 5 | Other (specify) | 
                                    
                    
                        | 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.