A POS device generates an electronic receipt in a format to which including clearance information indicating discount, and makes an electronic receipt center store the electronic receipt. When the electronic receipt center receives inquiry whether or not there is a store predicted to sell a clearance goods of a goods field designated among stores existing near a current location from a mobile terminal. The electronic receipt center searches the electronic receipt stored, and extracts an electronic receipt for the purchased clearance goods of a goods field designated at a store existing near the current location of the mobile terminal.