Introduction
In the field of accounting, particularly within managerial economics, understanding how firms in perfectly competitive markets make output decisions is crucial for analysing profitability and operational strategies. This essay explores the key aspects of these decisions, drawing from microeconomic principles. Specifically, it will examine how profits are calculated by comparing total revenue (TR) and total cost (TC), identify profits and losses using the average cost curve, explain the shutdown point, and determine the short-run production continuation price. By addressing these elements, the essay highlights the rational decision-making process for firms facing market-determined prices, using the example of a raspberry farm to illustrate concepts. This analysis is grounded in established economic theory, providing a sound foundation for undergraduate students studying accounting and economics.
Calculating Profits by Comparing Total Revenue and Total Cost
A perfectly competitive firm maximises profit by selecting the output quantity where the difference between TR and TC is greatest. TR is calculated as price (P) multiplied by quantity (Q), while TC includes both fixed and variable costs. As Sloman et al. (2018) explain, since the firm is a price-taker, its demand curve is perfectly elastic, meaning it can sell any quantity at the market price without affecting it.
Consider the raspberry farm example, where packs are sold at $4 each. From Table 8.1, at Q=70, TR=$280 and TC=$190, yielding a profit of $90. This is the maximum, as profits peak here before declining due to diminishing marginal returns, which cause TC to rise more steeply (Mankiw, 2018). Indeed, at lower outputs like Q=30, losses occur (-$6), and beyond Q=100, losses increase. Therefore, comparing TR and TC curves reveals the profit-maximising output, typically where marginal revenue (MR) equals marginal cost (MC), as this incremental approach aligns with the total method.
Identifying Profits and Losses with the Average Cost Curve
The average cost (AC) curve, or ATC, helps identify profits and losses by comparing it to the price level. In perfect competition, profit per unit is P minus ATC. If P > ATC, the firm earns economic profits; if P = ATC, zero profits; and if P < ATC, losses (Mankiw, 2018).
Using the raspberry data, at Q=70 and P=$4, if ATC is below $4, profits are positive. Graphically, the area between P and ATC represents profit or loss. For instance, at outputs where TR exceeds TC (Q=40 to 100), P > ATC, indicating profits. However, this method assumes short-run analysis, with limitations in long-run scenarios where entry/exit adjusts profits to zero (Sloman et al., 2018). Generally, it provides a clear visual tool for accountants to assess viability.
Explaining the Shutdown Point
The shutdown point occurs in the short run when a firm should cease production to minimise losses. This is where P equals average variable cost (AVC), as continuing would not cover variable costs, making losses worse than shutting down and only incurring fixed costs (Mankiw, 2018).
If P falls below AVC, the firm shuts down. For the raspberry farm, if P drops such that TR < TVC at all Q, shutdown is optimal. Sloman et al. (2018) note this decision avoids further variable cost accumulation, though it is temporary, pending market recovery.
Determining the Price for Short-Run Production Continuation
In the short run, a firm continues producing if P >= AVC, covering variable costs and contributing to fixed costs, even if incurring losses (Mankiw, 2018). Below AVC, shutdown is preferable. For example, if P=$2 for raspberries and AVC=$2.50 at optimal Q, shutdown minimises losses. This threshold ensures rational resource allocation, as argued by Sloman et al. (2018).
Conclusion
In summary, perfectly competitive firms decide output by maximising TR minus TC, using AC curves for profit identification, recognising the shutdown at P=AVC, and continuing if P >= AVC. These principles, illustrated by the raspberry farm, underscore efficient decision-making in accounting contexts. Implications include better cost management and strategic planning, though real-world frictions may limit applicability. Understanding these fosters analytical skills for aspiring accountants.
References
- Mankiw, N.G. (2018) Principles of Microeconomics. 8th edn. Cengage Learning.
- Sloman, J., Garratt, D. and Guest, J. (2018) Economics. 10th edn. Pearson.
