出口退税率调整的价格效应研究

An Empirical Study on the Price Effect of Export Tax Rebate Rate Adjustment

自2015年1月1日起,中国对1000多项商品的出口退税率进行调整。为分析此次调整对中国出口的影响,我们基于调整的内容和调整前后1年内中国2位数海关分类产品的出口价格指数,用倍差法估计了这次出口退税率调整对中国产品出口价格的影响。我们首先在一个简单的产品销售模型中引入增值税率和出口退税率,证明了一定条件下出口退税率上调会引起产品出口价格下降。随后,在基本回归分析中,我们发现出口退税率上调会引起中国产品出口价格指数在一年之内平均下降1. 38个百分点,这与我们理论模型中得出的结论一致。最后,我们在稳健分析结果中发现,出口退税率调整对产品出口价格指数的影响短期内并不显著,但是随着时间的延长这种影响的程度先增加后减小。

The Chinese government decided to adjust Export Tax Rebate Rate( ETR hereafter) of more than 1000 basic products in a notice posted online on December 31,2014. Based on this notice,we investigate the impact of ETR adjustment on export prices of Chinese products using"difference-in-difference"( DID hereafter) method and Chinese export price index of 2-digit HS products from January 2014 to December 2015. First,we develop a simple theoretical model to show the mechanism by which ETR adjustment might affect export price. From the model,we demonstrate that increases in ETR will lead to downward adjustment of export prices by exporters. In our basic regression,we find that Chinese export price index decreases on average by 1. 38 percentage points within a year after the official upward adjustment of ETR,which is consistent with our theoretical prediction. In addition,we conduct several robustness analyses,showing that the impact of ETR adjustment on export price index is not significant in the short run,but as we extend the horizon to 12 months,it grows significant,larger,and then smaller again.