A voided volume calculation unit automatically calculates a voided volume of a subject based on information for a weight value before voiding and information for the weight value after voiding that have been transmitted from a weight measurement unit. The memory unit takes the calculated voided volume of the subject as voided volume information, and makes association with additional information regarding voiding accepted by an additional information input accepting unit. Then, the memory unit records the pieces of information associated with each other as the voiding information. Therefore, it is possible to perform detailed management of the information regarding voiding.
