Cost per unit

Unit costs denote the costs that can be allocated to an allocation object. Companies determine, unit costs within cost unit accounting. Besides cost centre accounting and cost type accounting, this is the third and last subsystem of the accounting system. While cost type accounting collects the absolute amount and the value of the costs incurred by the company for the consumed resources, in cost centre accounting these costs are allocated to the individual cost centres in the company. In cost unit accounting it is ultimately determined the amount of resources consumed by a company in relation to the goods or services produced by the company and this resulting value represents the cost per unit (Taschner, Charifzadeh 2020, p. 73).

Benefits of using cost per unit

The unit costs, which are determined within the framework of a cost accounting system, are available to the management as a basis for decisions. Furthermore, they serve as a supporting instrument for the planning and controlling activities of the management or the controlling department with regard to the business activity or parts thereof (Vanderbeck 2010, p. 4).

Here, unit costs are used to generate important information for decision-making in the following areas:

• Information on the level of the cost per unit of a product is an essential decision-making tool in determining the selling price of the product. It should be high enough to cover all of the costs that are incurred by the allocation object. For example, the unit price is compared with the manufacturing costs of the product, but also with marketing and administration costs. At the same time, the owners of the company are usually expected to make a reasonable profit on the product, which must also be taken into account in setting the price (Vanderbeck 2010, p. 4).
• Therefore for management the interest in the cost per unit results from the fact that it is possible to derive the profit per unit produced or per service by equating the unit costs with the unit revenues (Taschner, Charifzadeh 2020, p. 73). It enables management to carry out analyses of the profitability of products and services and furthermore, this information can be used in the decision-making process to optimally allocate scarce resources according to profitability (Vanderbeck 2010, p. 4).
• Detailed unit cost information is also needed when facing competition in the market. In the market, companies compete on product prices. By using detailed unit cost information, you can analyse how you gain a price advantage over your competitor. In this way, a decision can be made about which measures need to be taken. On the one hand, an optimisation of the cost structure may be necessary, or a reduction of the sales price may solve the problem, whereby a mixture of both approaches is also possible. The goal is to ensure that the sale of the product or service generates a profit (Vanderbeck 2010, p. 4).
• In some companies or industries, it is common to submit bids for contracts. In this case, the cost per unit is essential information to determine a profitable and competitive offer price (Vanderbeck 2010, p. 4).

Determination of cost per unit

The general calculation of unit costs is carried out by means of an average calculation, which is why the term average cost is also used. As shown in the following formula, an absolute total cost amount is divided by the number of corresponding allocation objects. This makes it possible to calculate specific unit costs along the entire value chain, such as the unit production costs, the unit labour costs or also the unit costs in customer service, etc (Bhimani et al. 2015, p. 37).

Formula:

$\mathrm {{\frac {Total\ cost}{Number\ of\ products\ and\ services}}=Cost\ per\ unit}$

Example 1:

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathrm{\frac{9,800\ €}{100\ units}=9.80\ €\ per\ unit}}

As the previous formula and example illustrate in business practice, the majority of companies use absorption costing (also known as full cost accounting) when applying unit cost accounting. This approach is based on adding the fixed costs proportionally to the allocated objects in plus the variable unit costs in order to obtain the costs per unit. However, it should be noted that the total costs, which consist of the sum of the cost units, are the same as the total costs from cost accounting. Otherwise, this absorption costing approach could in some cases lead to erroneous decision outcomes between several alternatives. This can be avoided if the fixed costs used are allocated on the basis of the allocation objects of the corresponding alternatives. (Schuster 2021, p. 21).

Example 2

In the following examples, two alternatives are compared with each other. Two products are used in each scenario. Product 1 has variable unit costs of 200 € per unit, while product 2 has variable unit costs of 300 € per unit. The fixed costs are assumed to be 220,000 €. The two scenarios differ in the number of units of the two products. In scenario 1, 400 units of product 1 and 100 units of product 2 are planned. Scenario 2 assumes 200 units for product 1 and product 2.

Periodic costs Scenario 1

Variable cost	Product 1: 200 € * 400 units = 80,000 € Product 2: 300 € * 100 units = 30,000 € 80,000 € + 30,000 € = 110,000 €
Fixed cost	220,000 €
Total Cost	330,000 €

In scenario 1, one would assume a total cost of 330,000 € in the period. To switch to the unit cost level, we need the allocation percentage of the fixed costs. This is 220,000 €/110,000 € = 2 (200 %) for scenario 1.

Unit costs Scenario 1

Product 1	200 € + 200 € * 2 = 600 € per unit
Product 2	300 € + 300 € * 2 = 900 € per unit
Total Cost on basis of unit cost	600 € * 400 unit + 900 € * 100 unit = 330,000 €

Periodic costs Scenario 2

Variable cost	Product 1: 200 € * 200 units = 40,000 € Product 2: 300 € * 200 units = 60,000 € 40,000 € + 60,000 € = 100,000 €
Fixed cost	220,000 €
Total Cost	320,000 €

In scenario 2, one would assume a total cost of 320,000 € in the period. To switch to the unit cost level and we need the allocation percentage of the fixed costs again, otherwise cost allocations are no longer neutralised. This is 220,000 € /110,000 € = 2 (200 %) for scenario 2.

Unit costs Scenario 2

Product 1	200 € + 200 € * 2.2 = 640 € per unit
Product 2	300 € + 300 € * 2.2 = 960 € per unit
Total Cost on basis of unit cost	640 € * 200 unit + 960 € * 200 unit = 320,000 €

Scenario 2 generates lower costs and is therefore preferable from this point of view. In both scenarios, the total costs of the period and the total costs are the same and have therefore been calculated correctly and can therefore be used as a decision criterion (Schuster 2021, pp. 21–22).

Criticism of a cost per unit calculation

The previous example 2 illustrates that when using absorption costing in unit cost accounting, a possible source of error would be that the unit costs of the products were calculated in scenario 1 and then the same unit costs were also applied in the calculation of scenario 2. In this case, the total costs of the period in scenario 2 would no longer correspond to the total costs on the basis of the unit costs and would be therefore determined incorrectly. A further point of criticism can be found in the fact that the exclusive consideration of costs per unit takes place on a full cost basis. Because the costs contain a proportional distribution of fixed costs, costs are taken into account in the cost per unit that are incurred independently of product decisions. This fact could distort any make-or-buy decisions and the advantageousness of these could only be determined in periodic accounting and not in the unite cost accounting (Schuster 2021, p. 22).

References

• Bhimani, A., Horngren, C. T., Datar, S. M., Rajan M. (2015). Management and cost accounting. Harlow, England, New York: Pearson (Always learning).
• Schuster, P., Heinemann, M., Cleary, P. (2021). Management accounting. Cham, Switzerland: Springer (Springer texts in business and economics).
• Taschner, Andreas; Charifzadeh, Michel (2020). Management accounting in supply chains. Wiesbaden, Germany: Springer Gabler.
• Vanderbeck, Edward J. (2010). Principles of cost accounting. 15th ed. Mason OH: South-Western Cengage Learning.

Author: Martin Friesen