A service provider device includes key generation means, which generates a service public key for encrypting data and a secret key, and proxy key generation means, which inputs the service public key and the secret key and generates a proxy key. A data registration device includes encrypted data generation means, which generates encrypted data upon input of the service public key and data, and stores the generated encrypted data in a database. Proxy devices each includes encrypted portion statistical data generation means, which generates encrypted portion statistical data upon input of the proxy key with respect to the encrypted data stored in the database. An integrated data generation device includes encrypted statistical data generation means, which inputs the encrypted portion statistical data from each of the proxy devices, generates encrypted statistical data, and stores the generated encrypted statistical data in an integrated data storage device.
