Study finds 75% of US industries are more concentrated than 20 years ago, with the market share of the 4 largest firms having significantly increased for most US industries, while US markets have lost almost 50% of their publicly-traded firms

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Study finds 75% of US industries are more concentrated than 20 years ago, with the market share of the 4 largest firms having significantly increased for most US industries, while US markets have lost almost 50% of their publicly-traded firms