American industries have grown more concentrated over the last 40 years. In the absence of productivity innovation, this should lead to price hikes and output reductions, decreasing consumer welfare. With US census data from 1972 to 2012, I use price data to disentangle revenue from output. Industry-level estimates show that concentration increases are positively correlated to productivity and real output growth, uncorrelated with price changes and overall payroll, and negatively correlated with labor’s revenue share. I rationalize these results in a simple model of competition. Productive industries (with growing oligopolists) expand real output and hold down prices, raising consumer welfare, while maintaining or reducing their workforces, lowering labor’s share of output. (JEL D43, L13, D24, D33, D21, D42)

中文翻译：

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不断增长的寡头垄断、价格、产出和生产力

在过去的 40 年里，美国的工业变得更加集中。在缺乏生产力创新的情况下，这将导致价格上涨和产量减少，从而降低消费者福利。根据 1972 年至 2012 年的美国人口普查数据，我使用价格数据来区分收入与产出。行业层面的估计表明，集中度的提高与生产力和实际产出增长正相关，与价格变化和整体工资单无关，与劳动力的收入份额负相关。我将这些结果合理化为一个简单的竞争模型。生产性行业（寡头不断增加）扩大实际产出并压低价格，提高消费者福利，同时维持或减少劳动力，降低劳动力在产出中的份额。(JEL D43、L13、D24、D33、D21、D42)