| Value | Category | 
                                    
                    
                        | 1 | no education | 
                                    
                    
                        | 2 | std 1-4 | 
                                    
                    
                        | 3 | std 5-8 | 
                                    
                    
                        | 4 | form 1-2 | 
                                    
                    
                        | 5 | form  3-4 | 
                                    
                    
                        | 6 | adult literacy | 
                                    
                    
                        | 7 | training college | 
                                    
                    
                        | 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.