(also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business. (also called perpetual inventory system) inventory system where an on-going record is kept of the movement of stock into and out of a business.