In: Accounting
In perpetual method , we record each and every stock movement as and when they occur and maintain details of inventory , cost of goods sold at all the times. So Inventory and Cost of Sales keeps on changing for every transaction.
Whereas in periodic method , stock movements will be recorded periodical basis on physical verification of stocks and then cost of sales will be calculated by adding purchases to the opening stock value and reducing the inventory value. Inventory value is taken as the value of latest stock purchased.
Lets take the following Example
Stock statement as per perpetuity method | |||||||||
Purchases | Sales | Inventory | |||||||
DATE | Qty | Unit Cost($) | Total Cost($) | Qty | Unit Cost($) | Total Cost($) | Qty | Unit Cost($) | Total Cost($) |
Jul-02 | 600 | 12 | 7200 | 600 | 12 | 7200 | |||
Jul-05 | 200 | 13 | 2600 | 600 | 12 | 7200 | |||
200 | 13 | 2600 | |||||||
Jul-13 | 100 | 12 | 1200 | 500 | 12 | 6000 | |||
200 | 13 | 2600 | |||||||
Jul-21 | 325 | 14 | 4550 | 325 | 12 | 3900 | 175 | 12 | 2100 |
200 | 13 | 2600 | |||||||
325 | 14 | 4550 | |||||||
Total | 14350 | 5100 | 9250 | ||||||
Now lets calculate COGS as per periodic method | |||||||||
Units left in Stock | 700 | ||||||||
so value of inventory @ latest stock receipts | 325*14= | 4550 | |||||||
200*13= | 2600 | ||||||||
175*12= | 2100 | ||||||||
Total | 9250 | ||||||||
Value of cost of sales = Opening Stock+ Purchases -Inventory = 0 + 14350 -9250 = 5100 | |||||||||
So , Ultimate impact and result on cost of sales is same in both the cases but it is recommendatory to use perpetuity method as we can have more details about stock movements |