Policy and Social Implications of Declining Labor Shares

支付给劳动报酬的总收入份额或劳动份额的稳定性，一直是宏观经济模型的一个基本特征。这一假设对宏观经济动态、增长和收入不平等有着广泛的重要影响。然而，最近，在过去30年里，美国和世界上大多数国家的劳动收入占比出现了显著下降。过去几年，劳动收入占比下降一直是最重要的政策议题之一，引发了要求政府改变政策的呼声。该项目旨在开发工具，以更好地理解劳动收入占比下降的原因和影响。从经验上看，本研究项目旨在创建新的国有企业和企业劳动份额数据集，这些数据集将提供丰富的变化，有助于确定劳动份额下降的原因。事实证明，在投资品相对价格下降幅度最大的国家和行业，劳动收入占比的下降幅度最大。这表明在资本和劳动力高度可替代的环境中，资本生产部门的技术进步趋势的重要性。这些额外的新数据集将有助于证实资本成本下降导致美国劳动份额下降的程度，并区分这一解释和其他解释，如垄断力量或行业构成的变化或国际贸易的影响。区分这些替代方案将直接告诉我们，如果有的话，什么样的政策是有必要的，以应对不断下降的劳动份额。从理论上讲，该研究项目建立了一个框架，允许人们思考劳动份额下降对收入不平等的影响。该研究小组正在开发一个模型，将具有资本技能互补性的CES生产结构纳入具有异质代理的不完全市场模型，从而使人们能够理解跨要素份额和家庭间收入分配的联合动态。虽然近几十年来各国普遍出现了劳动收入占比下降和收入不平等加剧的现象，但在具有内生储蓄决策、内生劳动力供给、资本技能互补性和生命周期动态等现实特征的环境中，这些趋势之间的关系可能相当复杂。

The stability of the share of total income paid out as compensation to labor, or the labor share, has been a fundamental feature of macroeconomic models. This assumption carries with it a broad range of important implications for macroeconomic dynamics, growth, and income inequality. Recently, however, a significant decline has been documented in the labor share over the past 30 years in the United States and in most countries in the world. The declining labor share has been among the most important policy topics over the past several years, attracting calls for changes in government policies. The project aims to develop tools to better understand the causes and implications of the labor share decline.Empirically, this research project aims to create novel state-industry and firm datasets of labor shares that would offer rich variation useful for identifying the cause of the labor share decline. It has been demonstrated that labor share declines were greatest in countries and industries experiencing the largest declines in the relative price of investment goods. This suggests the importance for this trend of technological progress in capital producing sectors in an environment with highly substitutable capital and labor.These additional new datasets will help corroborate the extent to which cost of capital declines caused the decline of the U.S. labor share and to differentiate between this and alternative explanations, such as changes in monopoly power or industry composition or the influence of international trade. Differentiating among these alternatives will directly inform what types of policies, if any, may be warranted in response to the declining labor share.Theoretically, this research project builds a framework that allows one to think about the repercussions of the labor share decline for income inequality. This research team is developing a model that incorporates a CES production structure with capital-skill complementarity into an incomplete markets model with heterogeneous agents, allowing one to understand the joint dynamics of the distribution of income across factor shares and the distribution of income across households. While various countries have generally witnessed declining labor shares and increasing income inequality during recent decades, the relationship between these trends can be quite complicated in an environment with realistic features such as endogenous savings decisions, endogenous labor supply, capital-skill complementarity, and life-cycle dynamics.