AP MicroeconomicsMarket Structures
Long-Run Equilibrium
Long-run equilibrium in perfect competition occurs when firms earn zero economic profit, with price equal to minimum average total cost.
In the long run, firms enter or exit the market until economic profits are eliminated, driving price down to the lowest point on the average total cost curve. At this point, firms produce at productive efficiency and no incentive exists for new firms to enter or existing firms to exit.
Formula / Example
P = MC = min ATC
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Perfect Competition →
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Perfect Competition →
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