| Value | 
                    Category | 
                                                                            
                                    
                    
                        | 00 | 
                        NIU (not in universe)  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 10 | 
                        None  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 20 | 
                        Primary  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 21 | 
                        Primary, grade 1  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 22 | 
                        Primary, grade 2  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 23 | 
                        Primary, grade 3  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 24 | 
                        Primary, grade 4  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 25 | 
                        Primary, grade 5  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 26 | 
                        Primary, grade 6  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 30 | 
                        Junior high school  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 31 | 
                        Junior high school, grade 7  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 32 | 
                        Junior high school, grade 8  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 33 | 
                        Junior high school, grade 9  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 40 | 
                        Senior high school  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 41 | 
                        Senior high school, grade 10  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 42 | 
                        Senior high school, grade 11  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 43 | 
                        Senior high school, grade 12  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 50 | 
                        Technical/vocational  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 60 | 
                        University  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 61 | 
                        University, year 1  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 62 | 
                        University, year 2  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 63 | 
                        University, year 3  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 64 | 
                        University, year 4  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 65 | 
                        University, year 5  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 66 | 
                        University, completed  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 70 | 
                        Post-graduate and higher  | 
                        
                            
                        
                        
                        
                        
                            
                    
                            
            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.