To dispense with input and transmission of data attached to a receipt by a consumer through a computer.

A personal computer 2 used when a consumer purchases an article, a store terminal 5 disposed in a store selling the article, a center server 3 for receiving and processing data transmitted from the personal computer 2 and the store terminal 5, and a company computer 4 used for accessing the center server 3 by a company are interconnected through a network 7. This system is provided with a registering means for registering purchasing data of a consumer as a history into the center server 3 when the consumer purchases an article through the network 7 in an accounting method capable of identifying the consumer, a household account book producing means for producing a household account book based on the purchasing data, and a supplying means for producing and supplying purchasing information such as well-purchased article information matching to company needs using the household account book data.