INFORMATION PROCESSING UNIT, INFORMATION PROCESSING METHOD AND INFORMATION PROCESSING PROGRAM

PROBLEM TO BE SOLVED: To provide an information processing unit for enabling sales management until the end of a contract period by inputting information on an order reception through sales summing-up in the contract period of period contract type merchandise (service) only once.SOLUTION: Order reception information including a contract period of merchandise and the sum of merchandise is input. Billing data related with billings of merchandise is created based on the input order reception information and preliminarily registered billing information including a billing form of merchandise setting billing in monthly installments during the contract period or in one payment in a prescribed month during the contract period. Sales data related with the sales of merchandise is created based on the input order reception information and preliminarily registered sales information setting a sales calculation method of merchandise by the day, by the month or in one payment, and setting the summing-up method of the sales of merchandise by the month during the contact period or in a prescribed month during the contract period.