Under the first-in, first-out method, the cost of equivalent units of production is calculated by

Equivalent units of production is a term applied to the work-in-process inventory at the end of an accounting period. It is the number of completed units of an item that a company could theoretically have produced, given the amount of direct materials, direct labor, and manufacturing overhead costs incurred during that period for the items not yet completed. In short, if 100 units are in process but you have only expended 40% of the processing costs on them, then you are considered to have 40 equivalent units of production.

Equivalent units is a cost accounting concept that is used in process costing for cost calculations. It has no relevance from an operational perspective, nor is it useful for any other type of cost derivation other than process costing.

Equivalent units of production are usually stated separately for direct materials and all other manufacturing expenses, because direct materials are typically added at the beginning of the production process, while all other costs are incurred as the materials gradually work their way through the production process. Thus, the equivalent units for direct materials are generally higher than for other manufacturing expenses.

When assigning a cost to equivalent units of production, you typically assign either the weighted average cost of the beginning inventory plus new purchases to the direct materials, or the cost of the oldest inventory in stock (known as the first in, first out, or FIFO, method). The simpler of the two methods is the weighted average method. The FIFO method is more accurate, but the additional calculations do not represent a good cost-benefit trade off. Only consider using the FIFO method when costs vary substantially from period to period, so that management can see the trends in costs.

Example of Equivalent Units of Production

ABC International has a manufacturing line that produces large amounts of green widgets. At the end of the most recent accounting period, ABC had 1,000 green widgets still under construction. The manufacturing process for a green widget requires that all materials be sent to the shop floor at the start of the process, and then a variety of processing steps are added before the widgets are considered complete.  At the end of the period, ABC had incurred 35% of the labor and manufacturing overhead costs required to complete the 1,000 green widgets. Consequently, there were 1,000 equivalent units for materials and 350 equivalent units for direct labor and manufacturing overhead.

Knowing how to calculate equivalent units of production is an important tool for those in the business and accounting world. When thinking about how goods are manufactured and sent in a finished form to their destination, there are a lot of steps. There are costs involved at each step, from starting production to mid-production to finished production.

Tip

Knowing how to calculate equivalent units of production is an important tool in the business and accounting world. There are two ways to calculate this metric, known as the weighted average method or the first-in, first-out method.

Accountants use the term equivalent units to explain how costs are segmented between items that are still in production versus items that are in completed form. Many items are in continuous production, so without some way to calculate equivalent units, it would be difficult to determine how much money was tied up in production costs. Incomplete work must be accounted for on a regular basis so that a value can be placed on the incomplete work.

There is a simple formula that is used to calculate the equivalent units of production for those partially completed units. This formula not only applies to materials that are in continuous production, but also to labor costs and overhead costs.

Let’s say a parts maker is supposed to make 1,000 parts. At the end of the first quarter, there are 500 completed parts and 300 parts that are still in process. The parts maker’s best estimate is that these additional 300 parts are 50 percent completed. These parts are only half done, so they can’t be counted as finished parts, but the costs involved in making them need to be accounted for. If a report was created, it would indicate that there are 1,150 equivalent units of production.

Here’s the formula:

The number of partially completed units x percentage of completion = equivalent units of production

Plugging in the information that you have from the parts maker, there are 300 partially completed units. These 300 units are 50 percent completed.

300 x .5 = equivalent units of production

equivalent units of production = 150

These equivalent units are added to the 500 parts that are already done, and the total units of production come to:

500 + 150 = 650 equivalent units of production

The weighted average method to calculate equivalent units of production combines units and costs from the current period with units and costs from the prior period. The calculation is different for a weighted average. Here is the weighted average formula:

Total equivalent units for a cost component = A + B × C

WhereA = units transferred out to the next department/finished goodsB = units in closing work in process

C = percentage of completion with respect to the relevant cost component

Using the formula given in the first section (Number of partially completed units × percentage of completion = equivalent units), the equivalent units of production are transferred to the next department of finished goods plus the equivalent units in the department's ending work-in-process inventory.

Total equivalent units = 650 equivalent units of production + 300 + .5

Total equivalent units = 800

Note that, in the weighted average method, beginning work-in-process inventory is ignored. When you use weighted averages, all work accomplished in prior periods is not factored into the equations.

The second method of calculating equivalent units of production uses a FIFO method or First-in First-out. Businesses will first sell the finished inventory that they first receive, followed by any inventory they receive later, hence first in, first out.

Use the following equation for FIFO:

Equivalent Units of Production = equivalent units to complete beginning inventory + units started and completed during the period + equivalent units in ending work in process inventory.

Equivalent units to complete beginning inventory = units in beginning inventory × (100 percent − percentage completion of beginning inventory).

The entire equation can be further simplified to:

Equivalent units of production = units transferred out + equivalent units in ending work in process inventory − equivalent units in beginning inventory.

Calculate the units of production from both materials and conversion. Using FIFO, you'll have two percentages to determine for beginning and ending inventory.

Equivalent units under FIFO method are calculated using more variables than the previous example:

Equivalent units for each cost component = (100% − A) × B + C + D × E

Where,
A = percentage of completion at the end of last period

B = units in opening work in processC = units added/started and transferred outD = percentage of completion of units in closing work in process

E = units in closing work in process

Here’s a walkthrough of the formula using our parts example if there are 1,000 parts in beginning production during the month of March. During that accounting period (March), let’s say that an additional 4,000 parts are added to production. During March, 3,000 parts are completed and moved out of production. Let’s say there were 2,000 parts completed at the end of the last accounting period and that the parts- in-process are 30 percent done. This leaves:

A = 2,000B = 1,000C = 4,000

D = 30%

1,000 (beginning production)+ 4,000 (added to production) – 3,000 (parts completed) = 2,000 parts in production.

E = 2,000

To use the FIFO method, only the percentage of beginning parts completed during the accounting period is used, along with the production costs incurred in completing those units. You can use the same method for calculating the overhead costs and materials if you know the percentage of completion of each pricing factor.

Another acceptable method for determining unit cost under process costing is the first-in, first-out (FIFO) cost method. Under the FIFO method, we assume any units that were not completed last period (beginning work in process) are finished before anything else is started. The following table shows the differences between the weighted average method and the FIFO cost method:

Weighted Average FIFO
Units Completed and transferred out: Total units completed this period Total units finished from beginning work in process + units started and completed this period
Equivalent Units based on: Units completed this period + Units in Ending Work in Process Units from Beg. Work in Process completed + units started and completed + units in Ending Work in Process
Cost per Equivalent Unit based on: Beg. Work in Process Costs + Costs added this period Costs added this period only
Assign costs using: Equivalent Units x Cost per Equivalent Units for Units completed and units in ending Work in Process Beg. Work in Process Costs + Equivalent Units x cost per equivalent unit for units finished from Beg. Work In Process, Units started and completed and units in End. Work In Process

We will look at each item individually as we discuss the steps of process costing. Under either method, weighted average or FIFO, process costing consists of 5 steps:

  1. Physical Flow of Units
  2. Equivalent Units
  3. Cost per Equivalent Unit
  4. Assign Costs to Units Completed and Ending Work in Process Inventory
  5. Reconcile Costs

Physical Flow of Units

The physical flow of units is as follows under the weighted average method:

Units in Beg. WIP Units Completed and Transferred

+ Units Started this period

+ Units in End. WIP

= Total Units = Total Units

This is altered just slightly under the FIFO method as we must separate the items in units completed into Units Completed from beginning work in process and Units started and completed this period since under FIFO, we must finish anything from beginning work in process before we start something new. Under the FIFO, we the physical flow of units would be documented as:

Units in Beg. WIP Units Completed and Transferred:

+ Units Started this period

Beg. Work in Process Units Completed
= Total Units

+ Units started and Completed this period

= Units completed and transferred

+ Units in End. WIP

= Total Units

Just as in the weighted average method, the 2 Total Units figures must agree!

Equivalent Units of Production

Under the FIFO method, we will calculate equivalent units for 3 things: Units completed from beginning work in process, units started and completed this period and units remaining in ending work in process. This video will discuss the differences between the Weighted Average and FIFO methods for equivalent units (if you are comfortable with the weighted average method, skip to minute 4:06 to begin the discussion on the FIFO method).

Under the first-in, first-out method, the cost of equivalent units of production is calculated by

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Equivalent units for the period will be calculated as follows under FIFO (keep in mind, you may have different percent complete for materials, labor and overhead):

  1. Units from beginning work in process: you want to complete this units, so how much MORE effort will be needed to finish these units. You will calculate this as beginning work in process units x (100% – given % complete) to calculate the amount of additional work necessary to make the unit 100% complete.
  2. Units started and completed this period: take the units x 100% complete since they were started and completed they have received all of their materials, labor and overhead and will not receive any more since they are finished.
  3. Units in Ending work in process: just like with the weighted average method, we will take the ending work in process units x a given % complete.

To illustrate the computation of equivalent units under the FIFO method, assume the following facts (for simplicity we are using just one percent complete for materials, labor and overhead):

Beginning work in process inventory 3,000 units, 40% complete
Units started this period 10,000 units
Ending work in process inventory 5,000 units, 20% complete

The physical flow of units would be (calculate units started and completed as units started 10,000 – units in ending work in process 5,000):

Units in Beg. WIP 3,000 Units Completed and Transferred:
Units Started this period

10,000

Units from Beg. WIP 3,000
Total Units 13,000 Units started and completed

5,000

(10,000 – 5,000)
Total Units completed and txfr 8,000
Units in End. WIP

5,000

Total Units 13,000

The equivalent production for the period would be:

Units from beginning WIP [3,000 units x (100% – 40% complete)] 1,800
Units started and completed 5,000 units x 100% complete 5,000
Units in ending WIP 5,000 units x 20% complete

1,000

Total Equivalent Units 7,800

Cost per Equivalent Unit

Under the weighted average method, we use beginning work in process costs AND costs added this period. Under the FIFO method, we will only use the costs added this period. This video will explain the differences between the two approaches.

Under the first-in, first-out method, the cost of equivalent units of production is calculated by

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The formula we will use for calculating cost per equivalent unit under the FIFO Method is:

Current Costs added this period

÷ Total Equivalent Units

= Cost per Equivalent Units

Assign Costs

When we assign costs to units completed and transferred and units remaining in ending work in process under the FIFO method, we need the following items:

  1. Costs from beginning work in process: these were the costs we started the period with or the unfinished items from the previous period (no calculation required — just bring over the costs from beginning work in process). Remember, under FIFO, these are finished first so their costs must be passed along to completed units.
  2. Costs to complete beginning work in process: you will take the Equivalent units calculated for completing beginning work in process x the cost per equivalent unit. You will do this for materials, labor and overhead (or for conversion costs which is the both direct labor and overhead).
  3. Costs of units started and completed: you will take the equivalent units calculated for units started and completed x the cost per equivalent unit for materials, labor and overhead (or conversion).
  4. The sum of these 3 will be the cost of units completed and transferred which is also known as cost of goods manufactured. This amount is transferred to the next department or to finished goods and out of work in process for the units completed this period.
  5. Cost of units remaining in ending work in process: you will take the ending work in process equivalent units x the cost per equivalent unit for materials, labor and overhead (or conversion) just as we did under the weighed average method. This amount rolls over to be the next period’s beginning work in process inventory.

This video will provide a demonstration of cost assignment under the FIFO method.

Under the first-in, first-out method, the cost of equivalent units of production is calculated by

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Reconcile Costs

Finally, something is the same under FIFO and Weighted Average.

We want to make sure that we have assigned all the costs from beginning work in process and costs incurred or added this period to units completed and transferred and ending work in process inventory.

First, we need to know our total costs for the period (or total costs to account for) by adding beginning work in process costs to the costs incurred or added this period. Then, we compare the total to the cost assignment in step 4 for units completed and transferred and ending work in process to get total units accounted for. Both totals should agree.

The cost reconciliation would be:

Beg. Work in Process Cost

+ Costs added this period

= Total costs to account for
Cost assigned to units completed and transferred

+ Cost assigned to ending work in process inventory

= Total costs accounted for

In the next page, we will do a demonstration problem of the FIFO method for process costing.

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  • Equivalent Units. Authored by: Linda Williams. License: All Rights Reserved. License Terms: Standard YouTube License
  • Cost Per Equivalent Unit-- FIFO Method vs. Weighted-average Method . Authored by: Education Unlocked. Located at: https://youtu.be/P_Nwchc_pcs. License: All Rights Reserved. License Terms: Standard YouTube License
  • Cost Per Equivalent Unit, FIFO Method, Part 2 (Applying Costs) . Authored by: Education Unlocked. Located at: https://youtu.be/y1TLRSL9Yjo. License: All Rights Reserved. License Terms: Standard YouTube License