双轮驱动下中国经济增长的共同趋势与相依周期

The Common Trend and the Codependent Cycle of China's Economic Growth by the Two-wheel Drive

本文在供给侧和需求侧的双轮驱动下分解经济增长的共同趋势和相依周期,并在共同趋势和相依周期的约束下揭示供给侧和需求侧驱动力的相互影响。研究发现:(1)供给侧和需求侧的驱动力不仅各自推动经济增长,它们还相互作用,形成合力共同推动经济增长的长期趋势和短期周期。在供给侧和需求侧的驱动下,新常态时期经济增长的长期趋势和短期周期都处于下行阶段。(2)新常态下,需求侧支撑的趋势增长率低于供给侧推动的趋势增长率,但供给侧驱动力减弱的幅度大于需求侧驱动力的减弱幅度,因此,当前经济增速趋势下行过程中的供给侧因素更为重要。(3)整体而言,需求侧驱动力和供给侧驱动力存在正向的相互影响,但供给侧的人力资本积累不利于三大需求的增加,需求侧的投资增加不会显著带来供给侧的制度变迁、产业升级和人力资本积累的持续上升。稳定经济增长的宏观调控政策要以供给侧为主兼顾需求侧的双轮发力,同时还要特别关注供给侧和需求侧的相互影响。

The Chinese government has put a heavy emphasis on structural reforms on the supply side with economic restructuring at the core.Supplyside structural reforms ensure sustained economic growth.Demand management creates a favorable macroenvironment for supplyside structural reforms by appropriately expanding aggregate demand.Therefore,the supply and demand sides interact with each other to jointly promote economic growth.Cooperation and coordination between the supply and demand sides needs to be considered when decomposing the trend and cycle of Chinas economic growth.There are two main methods for decomposing the trend and cycle of economic growth:production function decomposition and statistical decomposition(Osman,2011;Andrei&Paun,2014).Production function decomposition starts from the supply side and has two advantages:it has a solid theoretical basis and can identify the structural input factors that affect the output trend.Statistical decomposition decomposes the data in a dataspeaking manner.According to real business cycle theory,if technology progress is a drifting random walk process(King et al.,1988),there are common deterministic and random elements to the trend components of actual output.Based on this,King et al.(1991)propose a decomposition method,KPSW,that imposes a cointegration relationship constraint on each variable in the model.This paper uses the KPSW method of Hecq et al.(2000,2006)to decompose the trend and cycle of GDP under the twowheel drive of the supply and demand sides.The sample period of this article is from 1984 to 2004.Labor input,physical capital,human capital,the upgrading of industrial structures,institutional changes and technological progress are selected as the driving forces on the supply side.Demandside drivers include consumption,investment and exports.In this paper,the supplyside driving force,demandside driving force and GDP are composed of cointegration vectors,creating an error correction model.We impose the Vahid&Engle(1993)codependence period constraint on the error correction model to obtain a quasierror correction model.This paper decomposes the trend and period of GDP based on this quasierror correction model and uses a generalized impulse response function to calculate the mutual influence of the twowheel driving force and its effect on economic growth.We find that the supplyand demandside driving forces directly promote economic growth and jointly promote the longterm trend and shortterm cycle of GDP.By the twowheel drive,the downward trend of economic growth during Chinas new normal period is the result of a combination of trend components and periodic components.Looking at the ability of the supply and demand sides to support the economic growth trend,the demand trend is smaller than the supply trend,but the gap between the two is shrinking.This decrease is due to the supplyside driving force falling faster than the demandside driving force.The accumulation of human capital is not conducive to the increase of the three major demands,and the accumulation of physical capital is not conducive to the increase of consumption.The remaining supplyside driving forces have a positive impact on demandside driving forces.Additionally,consumption and exports have a sustained positive effect on the supply side,but investment is not conducive to institutional changes,industrial upgrade and human capital accumulation.This study leads to several policy recommendations.Longterm macroeconomic control policies should focus on the supply side,concentrating on upgrading industrial structures and accumulating human capital.Shortterm macrocontrol policy should strive to expand total demand,focusing on the stimulation of consumption.