| Value | Category | 
                                    
                    
                        | -9 | don't know | 
                                    
                    
                        | -8 | refusal | 
                                    
                    
                        | 1 | there are no rewards | 
                                    
                    
                        | 2 | only top and middle management is rewarded | 
                                    
                    
                        | 3 | all staff is rewarded | 
                                    
                    
                        | 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.