| Value | Category | 
                                    
                    
                        | 1 | A card, which calculated tax, overtime pay and social insura | 
                                    
                    
                        | 2 | A payroll to pay wages only | 
                                    
                    
                        | 3 | Electronic card | 
                                    
                    
                        | 4 | Not any receipts | 
                                    
                    
                        | 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.