Types of Profit
AP MicroeconomicsΒ· Unit 3: Production, Cost, and the Perfect Competition Model, 3.2 ProfitΒ· 12 min read
1. Explicit and Implicit Costs: The Foundation of Profit Calculationsβ β ββββ± 3 min
All profit calculations rely on correctly separating costs into two mutually exclusive categories. AP exam questions almost always hide implicit costs as forgone income, so you will need to actively spot these values instead of pulling them directly from a listed expense table.
Explicit Cost
Direct, measurable out-of-pocket payments a firm makes to external suppliers, employees, or landlords.
Implicit Cost
The opportunity cost of using resources the firm already owns, with no corresponding cash transaction.
A cafΓ© owner uses their own unrented storefront space and quits a $60,000 per year job to run the business. They pay $20,000 per year for ingredients and $30,000 per year for part-time staff. Identify total explicit and total implicit costs.
- 1
First sum all direct out-of-pocket expenses to get total explicit cost:
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Next identify the two forgone opportunities that count as implicit costs. The unrented storefront would earn $24,000 per year if leased to another tenant, and the ownerβs old salary is $60,000 per year:
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Test your ability to separate cost types:
Which of the following is an implicit cost for a firm that owns its office building?
Monthly electricity bill
Forgone rental income from the building
Wages paid to full-time staff
Cost of office supplies
Reveal answer
Forgone rental income from the building βThe other three options are all direct out-of-pocket explicit costs.
Exam tip:
Implicit costs are never listed as 'expenses' on a standard income statement, so if a question mentions a prior salary or self-owned property, you must calculate the hidden opportunity cost.
2. Calculating Accounting Profitβ β ββββ± 2 min
Accounting profit is the standard profit value reported for tax and public financial disclosures, and it only accounts for explicit costs. This is the profit number most non-economists are familiar with, but it ignores critical opportunity costs.
A t-shirt shop generates $250,000 in annual total revenue, pays $120,000 for inventory, $40,000 for rent, and $60,000 for employee wages. Calculate accounting profit.
- 1
Sum all explicit costs first:
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Subtract total explicit costs from total revenue:
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3. Economic Profit and Normal Profitβ β β βββ± 4 min
Economic profit adjusts accounting profit to account for all opportunity costs, including implicit costs. This is the profit metric that drives resource allocation decisions in a market economy.
Normal Profit
The minimum level of profit required to keep a firm operating in its current market, which occurs exactly when economic profit equals zero.
Using the t-shirt shop data from the prior example, the owner gave up a $40,000 per year job to run the shop, and could earn $15,000 per year in interest if they sold their shop equipment and invested the proceeds. Calculate economic profit and state if the firm is earning normal profit.
- 1
Sum all implicit costs first:
- 2
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Subtract both explicit and implicit costs from total revenue, using the prior accounting profit value of $30,000 as a shortcut:
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Since economic profit is negative, the firm is not earning normal profit, and the owner would be better off closing the shop and taking their old job.
4. Profit Outcomes and Firm Behavior in Perfect Competitionβ β β βββ± 3 min
Economic profit levels are the primary signal that moves resources into and out of perfectly competitive markets, leading to long-run equilibrium at the zero economic profit point.
Positive economic profit: New firms are incentivized to enter the market, increasing supply and driving down prices until economic profit falls to zero
Zero economic profit (normal profit): No incentive for new firms to enter, no incentive for existing firms to exit, the market is in long-run equilibrium
Negative economic profit (economic loss): Existing firms will exit the market, decreasing supply and driving up prices until remaining firms earn zero economic profit
Confirm you understand market signals:
If firms in a competitive market are earning positive economic profit, what will happen in the long run?
Firms will exit the market
New firms will enter the market
Market supply will decrease
Market price will rise
Reveal answer
New firms will enter the market βEntry of new firms increases supply and pushes prices down until economic profit returns to zero.
5. Common Pitfalls
Wrong move:
Forgetting to subtract implicit costs when calculating economic profit
Why:
Students default to the familiar accounting profit formula out of habit
Correct move:
Always check if the question specifies economic vs accounting profit before selecting your formula
Wrong move:
Defining zero economic profit as a firm losing money or shutting down
Why:
Confusion between accounting and economic profit definitions
Correct move:
Zero economic profit means the firm earns positive accounting profit exactly equal to its total implicit opportunity costs
Wrong move:
Treating normal profit as an explicit out-of-pocket expense
Why:
Misreading textbook descriptions that frame normal profit as a cost
Correct move:
Normal profit is the minimum implicit return required to keep a firm operating, equal to the next best alternative outcome for the owner
Wrong move:
Double counting implicit costs in economic profit calculations
Why:
Adding implicit costs twice after writing the full TR minus explicit minus implicit formula
Correct move:
Verify that total economic cost = explicit + implicit before subtracting from total revenue
Wrong move:
Assuming positive accounting profit guarantees positive economic profit
Why:
Ignoring large implicit costs that can outweigh accounting gains
Correct move:
Always subtract all relevant opportunity costs before concluding economic profit is positive
6. Quick Reference Cheatsheet
Profit Type | Formula | Key Inputs | Exam Use Case |
|---|---|---|---|
Accounting Profit | TR - Total Explicit Costs | Only direct out-of-pocket expenses | Basic firm financial reporting |
Economic Profit | TR - (Explicit + Implicit Costs) | All opportunity costs including forgone income | Competitive market entry/exit analysis |
Normal Profit | Economic Profit = 0 | Accounting profit exactly equals total implicit costs | Long-run perfect competition equilibrium |
When this came up on past exams
AI-estimated based on syllabus patterns β cross-check with official past papers for accuracy. Use only as revision-focus signals.
- 2025 Β· MCQ Paper 1
Profit calculation with implicit cost
- 2024 Β· FRQ Paper 2
Identify implicit costs for a bakery
- 2023 Β· MCQ Paper 1
Zero economic profit definition
Going deeper
What's Next
Mastering types of profit is the critical building block for the rest of Unit 3, as you will apply these calculations to derive the firmβs marginal cost curve, average total cost curves, and the profit maximization rule for perfectly competitive firms. You will also use your understanding of zero economic profit to explain long-run market supply curves, and distinguish between accounting and economic profit when analyzing monopoly outcomes in later units. This topic is a frequent 3-5 point FRQ sub-part on past AP Micro exams, so solidifying your calculation fluency here will earn you easy points on test day.