Business decision analysis
Compare the future revenues and costs that differ between alternatives, including the value of constrained capacity. Sunk costs and unchanged allocations do not change the choice. State the assumptions before recommending a special order, make-or-buy or product-mix decision.
Compare what changes between alternatives
- Relevant amounts
- Future revenues and costs that differ between the options.
- Opportunity cost
- Contribution sacrificed by using a scarce resource here.
- Net benefit
- Incremental revenue - incremental cost - opportunity cost.
Exclude sunk costs and unchanged allocated costs. Include avoidable fixed costs and qualitative constraints.
See the decision
A special order with a dedicated setup
An idle-capacity order for 1,200 units offers $31 per unit. Incremental manufacturing and shipping cost is $23 per unit and a one-time setup costs $4,800. No regular sales are displaced and other fixed costs do not change.
USD for this order
- Revenue$37,200
- Incremental cost$32,400
- Profit increase$4,800
The order adds $4,800 under the stated assumptions. Confirm capacity and customer-pricing effects before accepting.
How to apply these ideas
1. Relevant costs
Include future differences; exclude sunk costs.
A historical study cost is unchanged whichever alternative is chosen. A future fixed cost can be relevant if the decision adds or avoids it. Classify each item by what changes, rather than automatically excluding every fixed cost.
Watch for: Using “fixed” as a synonym for “irrelevant.”
2. Capacity
Include contribution lost from the best forgone use.
At idle capacity, an extra order may displace nothing. At a bottleneck, it can replace profitable regular output. Compare contribution per constrained resource where products compete for the same scarce hours or material.
Watch for: Ranking products by contribution per unit when hours are constrained.
3. CVP
Separate contribution margin from operating profit.
Contribution margin equals revenue minus variable cost and first covers fixed costs. Break-even analysis assumes a relevant range, constant unit economics and, for a mix, a stable sales mix. Check whether those assumptions survive the proposed volume.
Watch for: Calling positive contribution the same as positive total profit.
4. Qualitative consequences
Test service, quality and market effects after the calculation.
An order may affect regular pricing, channel relationships or production reliability. Identify these conditions explicitly rather than using them as an unquantified excuse to ignore the economic comparison. A recommendation can be conditional on an operational check.
Watch for: Recommending solely from a margin while ignoring a stated constraint.
Study the topic
Business decision analysis: explanations and applications
Compare the revenues, costs and constraints that change between alternatives. This guide connects CVP, incremental decisions and pricing; the related lessons provide deeper calculations.
By MiloPrep editorial team. Original teaching explanations and illustrative cases; official curriculum references are listed below.
Define the alternatives and the time horizon first
A cost is relevant when it is future and differs between the alternatives, or represents an opportunity sacrificed. A historical purchase price is sunk. An allocated fixed cost can be relevant if the underlying resource is avoidable, but the allocation itself is not evidence of avoidability. Ask what actually changes in cash or resource use when the decision changes.
The time horizon matters. A lease may be unavoidable this month and avoidable at renewal. A manager may be able to redeploy labor even if immediate cash payroll does not fall. List the alternative use of released resources explicitly. A decision model that assumes “no alternative use” should not quietly claim an opportunity benefit later.
| Item | Include when | Common mistake |
|---|---|---|
| Past research or book value | A future consequence depends on the decision, not merely because it exists | Trying to recover a sunk amount by choosing a worse future option |
| Avoidable fixed expense | The commitment truly disappears under one alternative | Excluding all fixed costs automatically |
| Common overhead allocation | Underlying total resource cost changes | Treating a redistributed charge as a saving |
| Opportunity cost | An alternative use is sacrificed | Ignoring lost contribution at full capacity |
| Incremental revenue | The decision changes sales or price | Ignoring displaced regular sales |
Use contribution margin to connect volume and profit
Contribution margin per unit equals selling price minus variable cost per unit. It first covers fixed costs, then contributes to operating income. Break-even units equal fixed costs divided by unit contribution. For a target pretax profit, add that target to fixed costs before dividing. A target after-tax profit must first be converted to pretax profit under the stated tax assumptions.
Multi-product CVP requires a stated sales mix. Calculate the weighted contribution of the assumed bundle or mix, and keep it consistent when changing volume. Margin of safety measures the distance from break-even sales. Operating leverage describes the sensitivity of operating income around a given volume; the familiar percentage shortcut assumes unchanged prices, variable rates, fixed costs and mix.
Build special-order and make-or-buy models from changes
For a special order, begin with incremental revenue, production, shipping, customization and setup. If spare capacity is genuinely available, unchanged fixed manufacturing cost does not become incremental simply because a unit-cost report allocates it. At full capacity, include the contribution lost from regular sales or the cost of adding capacity.
For make-or-buy, compare avoidable manufacturing cost plus opportunity cost with the supplier price and all incremental purchasing, quality, logistics and transition costs. A lower quoted unit price is not enough when reliability or scarce capacity changes. Show the volume at which the alternatives are equal if the choice depends on a fixed-cost commitment.
Rank products by the constrained resource
When a single resource is binding, contribution per product unit can be misleading. Divide contribution by the amount of scarce resource each unit uses. Rank feasible production accordingly, subject to demand and any minimum commitments. If more than one constraint binds, a simple ranking may fail and a more complete optimization is required.
For a shutdown or product-line decision, identify which fixed costs disappear and what released capacity can earn. A segment loss after common allocations does not establish that closure improves company profit. For sell-or-process-further, compare additional selling value with further processing cost; joint cost incurred before split-off is unchanged by that later choice.
Connect pricing to demand, costs and strategic consequences
Cost-plus pricing applies a markup to a defined cost base. A 25% markup on cost differs from a 25% margin on selling price. Identify the denominator before computing the price. A target-cost approach starts from an achievable market price and required profit, then asks whether product design and operations can deliver the allowable cost.
The economic price decision also depends on demand response, competitor actions, capacity and customer relationships. A one-time price below full allocated cost may be sensible with idle capacity, but repeated discounting can change regular customers’ expectations or consume capacity later. A relevant-cost calculation should state those limitations instead of presenting the computed profit as the whole decision.
Work it through
Worked example: A special order with a dedicated setup
An idle-capacity order for 1,200 units offers $31 per unit. Incremental manufacturing and shipping cost is $23 per unit and a one-time setup costs $4,800. No regular sales are displaced and other fixed costs do not change.
| Incremental item | Amount |
|---|---|
| Revenue: 1,200 × $31 | $37,200 |
| Variable costs: 1,200 × $23 | -$27,600 |
| Order setup | -$4,800 |
| Incremental profit | $4,800 |
- 1
Contribution before setup = 1,200 × (31 - 23) = $9,600.
- 2
Deduct the order-specific fixed setup cost: 9,600 - 4,800 = $4,800.
The order adds $4,800 under the stated assumptions. Confirm capacity and customer-pricing effects before accepting.
Work through the alternatives
More worked cases: business decision analysis
Original teaching scenarios. Each case states its assumptions, shows the working and explains the limits of the conclusion.
Find the make-or-buy switching volume
Making requires $20 variable cost per unit and $60,000 avoidable annual fixed cost. Buying costs $26 per unit. Assume equal quality, no other costs and no alternative use of capacity.
| Annual volume | Make cost | Buy cost | Lower-cost option |
|---|---|---|---|
| 8,000 units | $220,000 | $208,000 | Buy by $12,000 |
| 10,000 units | $260,000 | $260,000 | Equal |
| 12,000 units | $300,000 | $312,000 | Make by $12,000 |
- Set 20Q + 60,000 = 26Q. The switching volume is 60,000 ÷ 6 = 10,000 units.
- At volumes above 10,000, the lower variable cost of making offsets the avoidable fixed commitment; below it, buying is cheaper.
What the result means: The recommendation is conditional on volume and avoidability. An unavoidable $60,000 cost would produce a different comparison.
A lower unit contribution can be the better use of capacity
Product A contributes $30 per unit and uses three machine-hours. Product B contributes $24 and uses one hour. Capacity is 600 hours; demand is at most 200 units of B and unlimited A. No other constraints or costs change. Show a continuous allocation, then check whole-unit feasibility.
| Step in the continuous model | Hours used | Contribution |
|---|---|---|
| Produce 200 B units first | 200 | $4,800 |
| Use remaining hours for A | 400 | $4,000 |
| Total | 600 | $8,800 |
- A earns $10 contribution per machine-hour; B earns $24. Fill the 200-unit B demand first.
- The remaining 400 hours earn 400 × $10 = $4,000 from A when fractional production is allowed. If whole units are required, produce 133 A units and leave one hour unused, earning $8,790 total.
What the result means: Name the divisibility assumption. The continuous model and whole-unit production model have slightly different feasible results.
Practice this topic
Check your understanding
Try each short application before opening its explanation. These are original learning checks, not official exam questions or a score prediction.
1. Price is $40, variable cost $25 and fixed cost $90,000. How many units produce $30,000 pretax operating income?
Show answer and explanation
8,000 units.
(90,000 + 30,000) ÷ (40 - 25) = 8,000. Break-even alone would be 6,000 units.
2. A product costs $80. What price gives a 20% margin on sales?
Show answer and explanation
$100.
Price - 80 = 20% × price, so price = 80/0.8. A 20% markup on cost would instead give $96.
3. A segment contributes $70,000 before fixed costs. Closing saves $40,000 traceable fixed costs, while $50,000 common allocation remains. Ignore other effects. Should it close on this evidence?
Show answer and explanation
No; closing reduces company profit by $30,000.
The $70,000 lost contribution exceeds the $40,000 saving. The common allocation may move to other segments but does not disappear.
Questions about business decision analysis
- Can a fixed cost be relevant?
- Yes. A supervisor hired only if an order is accepted is an incremental fixed cost. An unchanged allocation of head-office rent is not.
- Does a positive result always mean accept?
- It supports acceptance within the stated model. Check capacity, credit risk, product quality and effects on regular sales before making the actual business decision.
Sources and scope
Curriculum mapping: Part 2, Section C, Business Decision Analysis. The official outline assigns 25% to the entire domain, not to this individual technique. These are selected study notes, not complete curriculum coverage.
Official curriculum references establish scope and expected skills. The explanations, diagrams and numerical cases are independent teaching material from MiloPrep, not official questions or source-validated solutions. Curriculum references checked 2026-10-10.
- IMA Content Specification Outlines (effective September 2024) ↗
Supports: Part 2, Section C, beginning on printed page 11. Domain names, weights and curriculum boundaries.
- IMA Learning Outcome Statements (effective September 2024) ↗
Supports: Part 2, Section C, beginning on printed page 23. The calculations, analysis and professional judgments candidates are expected to perform.
Independent US CMA study material. Not affiliated with or endorsed by IMA. This covers management accounting, not medical-assistant certification or the separate ICMAI qualification.