The increased volume of sales has resulted in a number of errors in which customers were sent the wrong items. There have also been some delays in shipping because items that supposedly were in stock could not be found in the warehouse. Although a perpetual inventory is maintained, there has not been a physical count of inventory for two years. When an item is missing, the warehouse staff writes the information down in log book. Once a week, the warehouse staff uses the log book to update the inventory records.