CMA Part 2 Decision Analysis: Relevant Costs and Pricing

The core question: what changes?

Business Decision Analysis represents 25% of the Part 2 outline. Its central discipline is to compare alternatives using the future revenues and costs that change because of the decision. A cost already incurred is sunk. An unavoidable fixed cost usually remains regardless of the choice. A relevant cost is avoidable or otherwise different between alternatives. This distinction prevents accounting allocations from controlling a decision they do not economically affect.

Start every problem by stating the choice and time horizon. “Make or buy for the next month” differs from “close the department permanently.” A short-term decision may use spare capacity and avoidable costs; a long-term decision may include capacity replacement, strategic capability, or exit costs. The required answer may ask for a numeric advantage, a decision, or the most relevant additional fact.

Contribution and break-even logic

Contribution is sales revenue less variable costs. It contributes toward fixed costs and profit. For a single product, contribution per unit is selling price less variable cost per unit. Contribution margin ratio is contribution divided by sales. These measures help compare products, prices, and resource use, but they do not make fixed costs irrelevant in every decision.

Break-even volume equals fixed costs divided by contribution per unit under the model’s assumptions. Margin of safety measures how far expected sales exceed break-even sales. These calculations assume a defined relevant range and stable unit economics. If price, variable cost, product mix, or capacity changes, update the model rather than treating break-even as a permanent property of the business.

Special orders and spare capacity

For a one-time special order with spare capacity, compare incremental revenue with variable and other avoidable costs. Include order-specific setup, packaging, shipping, or quality costs. If regular customers are unaffected and capacity is truly available, an order priced below full cost may still add short-run profit. But a low price can damage normal pricing, channel relationships, or future demand if the offer becomes visible.

Worked example: a company can produce 12,000 units but expects regular demand of 10,000. Variable cost is $24 per unit. A buyer offers $31 for 1,500 units, requiring $3,000 of special packaging. Incremental benefit is (1,500 × $31) − (1,500 × $24) − $3,000 = $7,500. Because 2,000 units of capacity are unused, the order does not displace regular contribution under the stated facts. The decision would change if the order consumed capacity needed for higher-margin sales.

Opportunity cost and constrained resources

When a resource is constrained, using it for one product can displace another use. The opportunity cost is the contribution sacrificed from the best alternative. Rank products by contribution per unit of the scarce resource, not necessarily contribution per unit of product. The scarce resource may be labor hours, machine time, material, floor space, or a regulatory limit.

Suppose Product A yields $40 contribution and uses two machine hours, or $20 per machine hour. Product B yields $30 contribution and uses one machine hour, or $30 per machine hour. With machine time as the binding constraint and demand for both products, B should receive priority, subject to demand and other constraints. Choosing A because its contribution per finished unit is higher would use the scarce resource less effectively.

Make-or-buy decisions

A make-or-buy analysis compares the avoidable cost of internal production with the supplier price, plus quality, delivery, coordination, and strategic consequences. Allocated fixed overhead is not automatically saved when production stops. If the facility remains and the allocation simply moves to another department, it is not an avoidable cost. Conversely, if outsourcing permits closure or alternative use of capacity, those effects may matter.

The numerical comparison is only part of the decision. A low bid may depend on a fragile supplier, create intellectual-property exposure, reduce control over quality, or increase lead time. A higher internal cost may preserve critical expertise or supply resilience. Use the facts supplied and recognize when the question asks for a financial comparison versus a broader recommendation.

Pricing and product decisions

Pricing analysis depends on the decision context: short-term capacity, market competition, customer value, product life cycle, and strategic objective. Cost-plus pricing can provide a starting point but does not establish what customers will pay. A temporary price may cover incremental cost and still harm long-term positioning if customers expect it to continue.

For product mix, contribution per unit of a constrained resource guides short-run prioritization. For a product discontinuation, compare lost contribution with avoidable fixed costs and any effect on complementary products. A product with an accounting loss may still contribute toward unavoidable overhead; dropping it can make total profit worse if the assigned costs remain.

Relevant cost analysis with risk

Forecasts contain uncertainty. Sensitivity analysis changes one or more assumptions to show how the decision responds to price, volume, cost, or timing. Scenario analysis compares coherent sets of conditions. Expected values may be useful when probabilities are provided and the decision maker accepts the method, but a single expected amount can hide severe downside risk.

If a supplier offer saves cost only when delivery is on time, assess the cost of disruption and the availability of substitutes. If a price cut increases volume but strains capacity, evaluate contribution and bottlenecks. A financially attractive base case is less persuasive if it depends on an unsupported assumption.

Worked make-or-buy comparison

A company makes 5,000 components. Direct materials and labor total $18 each, variable overhead is $4 each, and allocated fixed overhead is $9 each. A supplier offers the components for $26 each. If buying eliminates only $15,000 of fixed cost, the relevant internal cost is 5,000 × $22 + $15,000 = $125,000. The purchase cost is 5,000 × $26 = $130,000, so making has a $5,000 financial advantage before qualitative effects.

A common error is comparing the supplier’s $26 with the full allocated cost of $31 and claiming a $25,000 saving. That assumes all fixed overhead disappears, contrary to the facts. Another error is excluding the $15,000 that is actually avoidable. The analysis changes if the freed capacity can earn contribution elsewhere; that opportunity benefit should be considered.

Study approach and exam traps

For each question, underline the alternative, time horizon, capacity condition, and costs that change. Label sunk, avoidable, unavoidable, and opportunity costs. Calculate the numeric difference, then state the decision in the requested form. Explain why full cost or allocated overhead does or does not matter.

Practice paired versions of the same scenario: spare capacity versus constrained capacity; fixed cost unavoidable versus avoidable; short-term order versus long-term market entry. The changed fact should change your analysis. That is more effective than memorizing a rule such as “accept any price above variable cost,” which is incomplete.

Pricing, product mix, and the decision horizon

A price that is acceptable for a one-time order with spare capacity may be unsustainable as a permanent price. In the short run, unused capacity can make incremental contribution the key calculation. In the long run, the business must recover the full set of operating costs, replace capacity, and consider how customers respond. Candidates should identify whether the scenario is temporary or strategic before recommending a price.

For product mix, calculate contribution per unit of the constrained resource. Then verify demand, minimum production commitments, and any second constraint. If one product earns $36 contribution using two bottleneck machine hours and another earns $25 using one hour, the second product generates more contribution per bottleneck hour ($25 versus $18). But if its demand is already satisfied or it requires a separate scarce input, the ranking alone does not settle the schedule.

A discount can increase volume yet lower total contribution if the incremental units do not cover their variable and incremental costs. It can also trigger customer substitution from full-price products. A good analysis calculates the volume needed to offset the lower unit margin and checks whether the market can plausibly support that volume. This prevents assuming that sales growth automatically means profit growth.

Decision checklist for an exam scenario

A reliable sequence is: name the alternatives; identify the decision horizon; list future revenues and costs that differ; remove sunk and unavoidable allocations; add opportunity costs; include qualitative and capacity constraints; calculate the incremental advantage; then state a recommendation. The calculation should match the requirement. If asked only for a financial advantage, do not bury the number under a long strategy essay. If asked for a recommendation, explain the relevant trade-off.

Watch for avoidable fixed costs. A fixed cost may be irrelevant when it continues under both alternatives, but relevant if the choice eliminates it. A supervisor salary, lease, or equipment cost cannot be classified by label alone. Ask whether it changes because of the decision. This is a frequent source of errors in shutdown and make-or-buy cases.

Also check for interactions. Dropping one product can reduce sales of a complementary product. Outsourcing can free capacity for a more profitable line. A price change can shift customers from another product. Include these effects when the case gives them; do not invent them when it does not.