| Value | 
                    Category | 
                                                                            
                                    
                    
                        | 1 | 
                        Rarely  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 2 | 
                        About half the time  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 3 | 
                        Most but not all lessons  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 4 | 
                        Every lesson  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 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.