Which method is commonly used for valuing inventory that assumes the oldest inventory items are sold first?

The method that assumes the oldest inventory items are sold first is commonly referred to as First In, First Out (FIFO). This approach operates under the principle that the earliest purchased goods are sold before those acquired later. As a result, FIFO aligns well with physical flow of inventory for many businesses, particularly those dealing with perishable goods, where older items need to be sold to prevent spoilage.

By using FIFO, when calculating the cost of goods sold, the cost associated with older inventory is matched with revenues generated from sales. This can lead to a higher asset value on the balance sheet during times of inflation, as the newest costs (often higher due to inflation) remain on the balance sheet while the older, typically lower costs, have been expensed.

This method stands in contrast to other inventory valuation approaches like Last In, First Out (LIFO), which assumes the most recently acquired inventory is sold first, potentially resulting in different financial implications depending on market conditions.