"the sum of all the measured or derived estimates of batch quantities of nuclear material on hand at a given time within a material balance area, obtained in accordance with specified procedures" (INFCIRC 153*). The physical inventory is determined by the facility operator as a result of a physical inventory taking and is reported to the IAEA in the physical inventory listing. The physical inventory is verified by the IAEA during a physical inventory verification inspection. The ending physical inventory for a material balance period is also the beginning physical inventory for the next material balance period.