Oligopoly is a common market form. As a quantitative outline of oligopoly, the four-firm concentration ratio is often utilized. This measure expresses the market industry share of the actual four largest firms in an industry as a percentage. Oligopolistic competition can promote many different outcomes. In a few situations, the firms may employ restrictive trade practices to boost prices and restrict production in a very similar way as a monopoly.
Oligopoly Market
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