| Value | Category | 
                                    
                    
                        | 1 | none | 
                                    
                    
                        | 2 | initial | 
                                    
                    
                        | 3 | primary | 
                                    
                    
                        | 4 | secondary | 
                                    
                    
                        | 5 | PROFESSIONAL BACHELOR | 
                                    
                    
                        | 6 | HIGHER, BACHELOR | 
                                    
                    
                        | 7 | HIGHER, MASTER | 
                                    
                    
                        | 8 | HIGHER, PhD | 
                                    
                    
                        | 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.