人民币汇率变动对加工贸易的影响:国内价值率提高的放大效应

The Rising Domestic Value Added Rate of China's Processing Exports and Its Amplification Effect on Renminbi Exchange Rate Elasticity

多数研究认为中国加工贸易的本土增值率较低,因而本币升值对"两头在外"的加工贸易进口和出口的影响不明显。我们计算发现,近20年间中国加工贸易的国内价值率呈上升趋势,而且要想正确评估人民币汇率对加工贸易进出口的影响方向和程度,就必须考虑国内价值率的变动。实证检验结果显示,人民币汇率升值能够显著降低加工贸易出口和进口,其长期弹性分别为-1.5和-1.0。进一步,由于加工贸易出口品中国外价值部分和国内价值部分受人民币汇率升值的影响方向相反,因此不同的国内价值率水平会使加工贸易进出口的汇率弹性发生改变。随着国内价值率的上升,加工贸易进出口的汇率弹性在样本期内经历了一个由正转负然后逐渐增大的过程,其中1995年的出口弹性和进口弹性分别为0.4和0.5,2014年则分别为-2.0和-1.4。

According to most of previous studies, both the raw materials production and the target sales market of China＇s processing trade are outside China, therefore domestic value added（DVA）rate of China＇s processing exports is relatively low, and renminbi （RMB）appreciation has muted effect on processing imports and exports. By calculating, it can be found that DVA rate of China＇s processing exports has demonstrated an upward trend during the last 20 years. Furthermore, in order to obtain more reasonable estimates of the effects of RMB exchange rate upon the direction and extent of processing imports and exports,the rising DVA rate must be taken into account. In this paper,empirical tests prove that RMB appreciation could significantly reduce the amount of processing imports and exports with the long-term elasticities of--1.5 and--1.0 respectively. What＇ more, owing to the opposite direction impact of RMB exchange rate upon the value of foreign inputs and domestic value of processing trade, thus various DVA rate will change the exchange rate elasticities of exports and imports. The test results indicate that exchange rate elasticities of processing imports and exports go from positive to negative and rise continually after 1998 with the increasing of DVA rate. To be exact, elasticities of processing exports and imports were 0.4 and 0. 5 respectively in 1995,and they were--2.0 and--1.4 respectively in 2014.