Why is a separate statement of cost of goods sold prepared rather than showing the full calculation on the income statement?

1. Cost of goods sold is worked out from the changes in all three inventory account balances during the period. 2. Those elements carry important information for managers, so they are not discarded. 3. They are too detailed and lengthy to present directly on the income statement, so a separate statement holds them. 4. Only the final cost of goods sold figure from that statement appears on the income statement. 5. Inventory balances, not the cost of goods sold calculation, are what appear on the balance sheet. _Source: Jonick, Principles of Managerial Accounting (UNG Press, CC BY-SA 4.0), section 1.3.1 Financial Reporting for a Manufacturer_