The customs shall exempt import duties tax for the import products and tax on the added value of products in accordance with the provisions on processing imported raw materials and parts and the real export volume of the processed products .

海关按照进料加工的有关规定，以实际加工出口数量，免征进口关税和进口 环节产品税、 增值 税。

The study finds that the tax burden has significant and positive effect on the hidden economy ( added value and intermediate input ) .

研究发现， 税收负担与隐性经济（ 增加 值和中间投入）显著正相关。