A control section edits a complete flow line as an entire trajectory in a sales area for each customer, based on data for a flow line generated from a camera image obtained by shooting the sales area. The complete flow line is reproduced as trajectories of customers by a display section. The control section accepts input of information on transaction settlements by the customers. When the information is input through an input section, it is added to the complete flow line data of the customers being reproduced and is stored into a complete flow line database. The control section matches the complete flow line data stored in the complete flow line database with transaction data specified by the information on the transaction settlements added to the complete flow line data.