利率走势、财富异质性与贫富差距——基于资产结构视角的理论分析与实证检验

Interest Rate Trend,Wealth Heterogeneity and the Poverty Gap——Theoretical Analysis and Empirical Test from the Perspective of Asset Structure

全球利率长期下降以及负利率政策对宏观经济产生了深远的影响,其中之一是影响贫富差距。本文构建了一个包含富人和穷人的财富异质性模型,并借鉴消费恩格尔系数设计了衡量财富结构的“投资恩格尔系数”,即货币性资产占总金融资产的比重。与消费恩格尔系数相似,收入越低和财富越少的阶层,投资恩格尔系数越高。在异质性资产结构下,当利率不断走低时,以公允价值计量的富人的财富会大幅升值,穷人则相对较难受益,导致财富差距进一步扩大。该模型较好地解释了国际金融危机和新冠肺炎疫情发生后,全球货币宽松、利率走低尤其是负利率引发的贫富差距恶化问题。本文搜集了57个国家40年的面板数据进行实证检验,检验结果较为显著地验证了理论模型的结论。

In the context of global long-term interest rate decline,this paper studies the transmission mechanism of wealth heterogeneity on wealth differentiation.Firstly,this paper explains the gap between rich and poor caused by monetary easing and interest rate reduction theoretically by constructing a model that divides the rich and poor classes according to the structure of assets and liabilities.Secondly,this paper collects 40-year panel data from 57 countries to verify the widening effect of asset and liability structure differences on the gap between the rich and the poor with the influence of falling interest rates.The results show that the trend towards lower interest rate will further widen the gap between the rich and the poor in a country,and this widening effect is more obvious in developing countries.Through further analysis,this paper finds that lower interest rate trend will further widen the wealth gap through"investment Engel’s coefficient".On this basis,this paper takes into account the differences in financing ability and investment ability,and finds that these differences have asymmetric effects on the asset end and the liability end,thus magnifying the deterioration of the gap between the rich and the poor caused by low interest rates.Based on the research conclusions of this paper,three suggestions are put forward.Firstly,when considering the transmission mechanism of monetary policy,different wealth structures should be considered to produce different welfare effects when the policy interest rate decreases.Secondly,policy makers should pay attention to the long-term structural problem of worsening the wealth gap caused by low interest rates when formulating monetary policies.Thirdly,in the process of implementing counter-cyclical policies,the government should prudently use the policy tools of low and negative interest rates to guide the trend of interest rates to an appropriate level suitable for high-quality development of the real economy and prevent excessive flattening or even inverted yield curve.