| Value | Category | 
                                    
                    
                        | 1 | Primary | 
                                    
                    
                        | 2 | preparatory | 
                                    
                    
                        | 3 | general secondary | 
                                    
                    
                        | 4 | vocational sec. | 
                                    
                    
                        | 5 | above intermediate | 
                                    
                    
                        | 6 | bachelor | 
                                    
                    
                        | 7 | high diploma | 
                                    
                    
                        | 8 | master’s | 
                                    
                    
                        | 9 | PhD | 
                                    
                    
                        | 96 | other | 
                            
            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.