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Accountancy/Cost Flow Assumptions
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Cost Flow Assumptions
Cost flow assumptions affect the more important Income Statement and less important Balance Sheet
Assume that the most recent cost is most relevant cost
Specific Identification
Keeps track of the cost of each, specific good sold
The Good
Perfect matching of costs of goods to goods sold
The Bad
Often impossible or too costly
Allows manipulation by management
FIFO
First-In-First-Out
Assigns first costs incurred to COGS (Cost of Goods Sold) on the Income Statement
The Good
Disallows manipulation by management
Cost flow agrees with ideal, physical flow of goods
Counter-Argument – Agreement of cost flow and ideal, physical flow of goods is not important
The Bad
Uses the least relevant cost for the Income Statement
Underestimates or overestimates cost of goods sold if prices are rising or falling, respectively
LIFO
Last-In-First-Out
Assigns last costs incurred to COGS on the Income Statement
The Good
Disallows manipulation by management
Uses the most relevant cost for the Income Statement
The Bad
Underestimates or overestimates cost of goods sold if prices are falling or rising, respectively
Cost flow disagrees with ideal, physical flow of goods
Counter-Argument – Agreement of cost flow and ideal, physical flow of goods is not important
Weighted Average
Assigns average cost incurred to COGS on the Income Statement
The Good
Disallows manipulation by management
Better estimation of the cost of goods sold than FIFO or LIFO if prices are rising or falling
The Bad
Tends to ignore extreme costs of inventory
There is no theoretical reasoning for using this method
Notes
LIFO and Weighted Average cost flow assumptions may yield different end inventories and COGS in a perpetual inventory system than in a periodic inventory system due to the timing of the calculations. In the perpetual system, some of the oldest units calculated in the periodic units-on-hand ending inventory may get expended during a near inventory exhausting individual sale, in the LIFO system; in the weighted average system, in the perpetual system, each sale moves the weighted average, so it is a moving weighted average for each sale, whereas in the periodic system, it is only the weighted average of the cost the beginning inventory, the sum cost of all the purchases, less the cost of the inventory , divided by the sum of the beginning units and the total units purchased.