Hello All,
I hope all are
doing well.
After long time,
again I am posting some concept of inventory calculation methods, this concepts
are very useful and very common.
1. The Weighted
Average Method | Weighted Average Costing
Weighted Average
Method Overview
The weighted average
method is used to assign the average cost of production to a product. Weighted
average costing is commonly used in situations where:
- Inventory items are so
intermingled that it is impossible to assign a specific cost to an
individual unit.
- The accounting system is not
sufficiently sophisticated to track FIFO or LIFO inventory layers.
- Inventory items are so
commoditized (i.e., identical to each other) that there is no way to
assign a cost to an individual unit.
When using the
weighted average method, divide the cost of goods available for sale by the
number of units available for sale, which yields the weighted-average cost per
unit. In this calculation, the cost of goods available for sale is the sum of
beginning inventory and net purchases. You then use this weighted-average
figure to assign a cost to both ending inventory and the cost of goods sold.
The net result of
using weighted average costing is that the recorded amount of inventory on hand
represents a value somewhere between the oldest and newest units purchased into
stock. Similarly, the cost of goods sold will reflect a cost somewhere between
that of the oldest and newest units that were sold during the period.
The weighted average
method is allowed under both generally accepted accounting principles and
international financial reporting standards.
Weighted Average
Costing Example
Milagro Corporation
elects to use the weighted-average method for the month of May. During that
month, it records the following transactions:
|
Quantity
Change
|
Actual
Unit Cost
|
Actual
Total Cost
|
Beginning inventory
|
+150
|
$220
|
$33,000
|
Sale
|
-125
|
--
|
--
|
Purchase
|
+200
|
270
|
54,000
|
Sale
|
-150
|
--
|
--
|
Purchase
|
+100
|
290
|
29,000
|
Ending inventory
|
=
175
|
|
|
The actual total cost of all purchased or beginning inventory units in the
preceding table is $116,000 ($33,000 + $54,000 + $29,000). The total of all
purchased or beginning inventory units is 450 (150 beginning inventory + 300
purchased). The weighted average cost per unit is therefore $257.78 ($116,000 ÷
450 units.)
The ending inventory
valuation is $45,112 (175 units × $257.78 weighted average cost), while the
cost of goods sold valuation is $70,890 (275 units × $257.78 weighted average
cost). The sum of these two amounts (less a rounding error) equals the $116,000
total actual cost of all purchases and beginning inventory.
In the preceding
example, if Milagro used a perpetual inventory system to record its inventory
transactions, it would have to recompute the weighted average after every
purchase. The following table uses the same information in the preceding
example to show the recomputations:
|
Units
on Hand
|
Purchases
|
Cost
of Sales
|
Inventory
Total
Cost
|
Inventory
Moving- Average
Unit Cost
|
Beginning inventory
|
150
|
$
--
|
$
--
|
$33,000
|
$220.00
|
Sale (125 units @
$220)
|
25
|
--
|
27,500
|
5,500
|
220.00
|
Purchase (200 units
@ $270)
|
225
|
54,000
|
--
|
59,500
|
264.44
|
Sale (150 units @
$264.44)
|
75
|
--
|
39,666
|
19,834
|
264.44
|
Purchase (100 units
@ $290)
|
175
|
29,000
|
--
|
48,834
|
279.05
|
Note that the cost of goods sold of $67,166 and the ending inventory balance of
$48,834 equal $116,000, which matches the total of the costs in the original
example. Thus, the totals are the same, but the moving weighted average
calculation results in slight differences in the apportionment of costs between
the cost of goods sold and ending inventory.
2. Moving Average Inventory
Method
Moving
Average Inventory Method Overview
Under the moving
average inventory method, the average cost of each inventory item in stock is
re-calculated after every inventory purchase. This method tends to yield
inventory valuations and cost of goods sold results that are in-between those
derived under the first in, first out (FIFO) method and the last
in, first out (LIFO)
method. This averaging approach is considered to yield a safe and conservative
approach to reporting financial results.
The calculation
is the total cost of the items purchased divided by the number of items in
stock. The cost of ending inventory and the cost of goods sold are then set at
this average cost. No cost layering is needed, as is required for the FIFO and
LIFO methods.
Since the moving
average cost changes whenever there is a new purchase, the method can only be
used with a perpetual
inventory tracking system; such a system keeps up-to-date records of
inventory balances. You cannot use the moving average inventory method if you
are only using a periodic
inventory system, since such a system only accumulates information at the
end of each accounting period, and does not maintain records at the individual
unit level.
Also, when
inventory valuations are derived using a computer system, the computer makes it
relatively easy to continually adjust inventory valuations with this method.
Conversely, it can be quite difficult to use the moving average method when
inventory records are being maintained manually, since the clerical staff would
be overwhelmed by the volume of required calculations.
Moving
Average Inventory Method Example
Example #1:
ABC International has
1,000 green widgets in stock as of the beginning of April, at a cost per unit
of $5. Thus, the beginning inventory balance of green widgets in April is
$5,000. ABC then purchases 250 additional greeen widgets on April 10 for $6
each (total purchase of $1,500), and another 750 green widgets on April 20 for
$7 each (total purchase of $5,250). In the absence of any sales, this means
that the moving average cost per unit at the end of April would be $5.88, which
is calculated as a total cost of $11,750 ($5,000 beginning balance + $1,500
purchase + $5,250 purchase), divided by the total on-hand unit count of 2,000
green widgets (1,000 beginning balance + 250 units purchased + 750 units
purchased). Thus, the moving average cost of the green widgets was $5 per unit
at the beginning of the month, and $5.88 at the end of the month.
We will repeat
the example, but now include several sales. Remember that we recalculate the
moving average after every
transaction.
Example #2:
ABC International has
1,000 green widgets in stock as of the beginning of April, at a cost per unit
of $5. It sells 250 of these units on April 5, and records a charge to the cost
of goods sold of $1,250, which is calculated as 250 units x $5 per unit. This
means there are now 750 units remaining in stock, at a cost per unit of $5 and
a total cost of $3,750.
ABC then
purchases 250 additional green widgets on April 10 for $6 each (total purchase
of $1,500). The moving average cost is now $5.25, which is calculated as a
total cost of $5,250 divided by the 1,000 units still on hand.
ABC then sells
200 units on April 12, and records a charge to the cost of goods sold of
$1,050, which is calculated as 200 units x $5.25 per unit. This means there are
now 800 units remaining in stock, at a cost per unit of $5.25 and a total cost
of $4,200.
Finally, ABC buys
an additional 750 green widgets on April 20 for $7 each (total purchase of
$5,250). At the end of the month, the moving average cost per unit is $6.10,
which is calculated as total costs of $4,200 + $5,250, divided by total
remaining units of 800 + 750.
Thus, in the
second example, ABC International begins the month with a $5,000 beginning
balance of green widgets at a cost of $5 each, sells 250 units at a cost of $5
on April 5, revises its unit cost to $5.25 after a purchase on April 10, sells
200 units at a cost of $5.25 on April 12, and finally revises its unit cost to
$6.10 after a purchase on April 20. You can see that the cost per unit changes
following an inventory purchase, but not after an inventory sale
3. Accounting
Inventory Methods
Inventory includes
the raw materials, work-in-process, and finished goods that a company has
on hand for its own production processes or for sale to customers. Inventory is
considered an asset, so the accountant must consistently use a valid method for
assigning costs to inventory in order to record it as an asset.
The valuation of
inventory is not a minor issue, because the accounting method used to create a
valuation has a direct bearing on the amount of expense charged to the cost of
goods sold in an accounting period, and therefore on the amount of income
earned. The basic formula for determining the cost of goods sold in an
accounting period is:
Beginning
inventory + Purchases - Ending inventory = Cost of goods sold
Thus, the cost of
goods sold is largely based on the cost assigned to ending inventory, which
brings us back to the accounting method used to do so. There are several
possible inventory costing methods, which are:
- Specific identification method. Under this approach, you
separately track the cost of each item in inventory, and charge the
specific cost of an item to the cost of goods sold when you sell the
specific item to which that cost has been assigned. This approach requires
a massive amount of data tracking, so it is only usable for very
high-cost, unique items, such as automobiles or works of art. It is not a
viable method in most other situations.
When you buy
inventory from suppliers, the price tends to change over time, so you end up
with a group of the same item in stock, but with some units costing more than
others. As you sell items from stock, you have to decide on a policy of whether
to charge items to the cost of goods sold that were presumably bought first, or
bought last, or based on an average of the costs of all items in stock. Your
choice of a policy will result in using either the first in first out method
(FIFO), the last in first out method (LIFO), or the weighted average method.
The following bullet points explain each concept:
- First in, first out method. Under the FIFO method, you are
assuming that items bought first are also used or sold first, which also
means that the items still in stock are the newest ones. This policy
closely matches the actual movement of inventory in most companies, and so
is preferable simply from a theoretical perspective. In periods of rising
prices (which is most of the time in most economies), assuming that the
earliest units bought are the first ones used also means that the least
expensive units are charged to the cost of goods sold first. This means
that the cost of goods sold tends to be lower, which therefore leads to a
higher amount of operating earnings, and more income taxes paid. Also, it
means that there tend to be fewer inventory layers than under the LIFO
method (see next), since you will continually use up the oldest layers.
- Last in, first out method. Under the LIFO method, you are
assuming that items bought last are sold first, which also means that the
items still in stock are the oldest ones. This policy does not follow the
natural flow of inventory in most companies; in fact, the method is banned
under International
Financial Reporting Standards. In periods of rising prices, assuming
that the last units bought are the first ones used also means that the
cost of goods sold tends to be higher, which therefore leads to a lower
amount of operating earnings, and fewer income taxes paid. There tend to
be more inventory layers than under the FIFO method, since the oldest
layers may not be flushed out for years.
- Weighted average method. Under the weighted average
method, there is only one inventory layer, since the cost of any new
inventory purchases are rolled into the cost of any existing inventory to
derive a new weighted average cost, which in turn is adjusted again as
more inventory is purchased.
Both the FIFO and
LIFO methods require the use of inventory layers, under which you have a separate
cost for each cluster of inventory items that were purchased at a specific
price. This requires a considerable amount of tracking in a database, so both
methods work best if inventory is tracked in a computer system.
4. FIFO vs. LIFO
Accounting
FIFO and LIFO are
cost layering methods used to value the cost of goods sold and ending
inventory. FIFO is a contraction of the term "first in, first out,"
and means that the goods first added to inventory are assumed to be the first
goods removed from inventory for sale. LIFO is a contraction of the term
"last in, first out," and means that the goods last added to
inventory are assumed to be the first goods removed from inventory for sale.
Why use one method
over the other? Here are some considerations that take into account the fields
of accounting, materials flow, and financial analysis:
Issue
|
FIFO
Method
|
LIFO
Method
|
Materials flow
|
In most
businesses, the actual flow of materials follows FIFO, which makes this a
logical choice.
|
There are few
businesses where the oldest items are kept in stock whiler newer items are
sold first.
|
Inflation
|
If costs are
increasing, the first items sold are the least expensive, so your cost of
goods sold decreases, you report more profits, and therefore pay a larger
amount of income taxes in the near term.
|
If costs are
increasing, the last items sold are the most expensive, so your cost of goods
sold increases, you report fewer profits, and therefore pay a smaller amount
of income taxes in the near term.
|
Deflation
|
If costs are
decreasing, the first items sold are the most expensive, so your cost of
goods sold increases, you report fewer profits, and therefore pay a smaller
amount of income taxes in the near term.
|
If costs are
decreasing, the last items sold are the least expensive, so your cost of
goods sold decreases, you report more profits, and therefore pay a larger
amount of income taxes in the near term.
|
Financial reporting
|
There are no GAAP or IFRS restrictions
on the use of FIFO in reporting financial results.
|
IFRS does not all
the use of the LIFO method at all. The IRS allows the use of LIFO, but if you
use it for any subsidiary, you must also use it for all parts of the
reporting entity.
|
Record keeping
|
There are usually
fewer inventory layers to track in a FIFO system, since the oldest layers are
continually used up. This reduces record keeping.
|
There are usually
more inventory layers to track in a LIFO system, since the oldest layers can
potentially remain in the system for years. This increases record keeping.
|
Reporting
fluctuations
|
Since there are few
inventory layers, and those layers reflect recent pricing, there are rarely
any unusual spikes or drops in the cost of goods sold that are caused by
accessing old inventory layers.
|
There may be many
inventory layers, some with costs from a number of years ago. If one of these
layers is accessed, it can result in a dramatic increase or decrease in the
reported amount of cost of goods sold.
|
In general, LIFO accounting is not recommended, for the following reasons:
- It is not allowed under IFRS, and
a large part of the world uses the IFRS framework.
- The number of layers to track can
be substantially larger than would be the case under FIFO.
- If old layers are accessed, costs
may be charged to expense that vary substantially from current
costs.
The basic concept
underlying perpetual LIFO is the last in, first out (LIFO) cost layering
system. Under LIFO, you assume that the last item entering inventory is the
first one to be used. For example, consider stocking the shelves in a food
store, where a customer purchases the item in front, which was likely to be the
last item added to the shelf by a clerk. These LIFO transactions are recorded
under the perpetual
inventory system, where inventory records are constantly updated as
inventory-related transactions occur.
The results of a
perpetual LIFO system may vary from those generated by a periodic LIFO system,
because inventory records in a periodic system
are only updated at the end of a reporting period.
The only
difference between the two cost flow concepts is how rapidly a costing layer is
stripped away or replenished in the costing database. Under perpetual LIFO,
there can be a great deal of this activity throughout a reporting period, with
inventory layers being added and eliminated potentially as frequently as every
day. This means that the costs at which items are sold could vary throughout
the period, since costs are being drawn from the most recent of a constantly
varying set of cost layers.
Under a periodic
LIFO system, however, layers are only stripped away at the end of the period,
so that only the very last layers are depleted.
For example, ABC
International acquires 10 green widgets on January 15 for $5, and acquires
another 10 green widgets at the end of the month for $7. ABC sells five green
widgets on January 16. Under a perpetual LIFO system, you would charge the cost
of the five widgets sold on January 16 to the cost of goods sold as soon as the
sale occurs, which means that the cost of goods sold is $25 (5 units x $5
each). Under a periodic LIFO system, you would wait until the end of the month
and then record the sale, which means that you remove five units from the last
layer recorded at the end of the month, which results in a charge to the cost
of goods sold of $35 (5 units x $7 each).
In a period of
continually increasing prices, a periodic LIFO system will result in the
highest cost of goods sold and therefore the lowest net income, since it will
always use up the most recently purchased inventory first. Conversely, in a
period of decreasing prices, the reverse would be true.
The costing
results of a perpetual LIFO system are more common than a periodic LIFO system,
since most inventory is now tracked using computerized systems that maintain
inventory records on a real-time basis.
Thank Y0u - Subrat Kumar