| Value | Category | 
                                    
                    
                        | -9 | Don't Know | 
                                    
                    
                        | 1 | Primary | 
                                    
                    
                        | 2 | Combined | 
                                    
                    
                        | 3 | Intermediate | 
                                    
                    
                        | 4 | Secondary | 
                                    
                    
                        | 5 | Special needs | 
                                    
                    
                        | 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.