WITS TRAINS — MFN Applied TariffsWITS TRAINS 最惠国适用关税

Country-year panel of the simple-average Most-Favoured-Nation (MFN) applied tariff, built from the World Bank WITS / UNCTAD TRAINS product-line tariff files (ad-valorem equivalents included). Each observation is a reporting economy in a given year; the value is the unweighted mean of the applied tariff across all HS product lines reported that year.

The series is a standard measure of an economy's overall tariff protection and supports analysis of trade-protectionism and supply-chain risk.

各国-年度最惠国（MFN）适用关税简单平均面板，来自世界银行 WITS / UNCTAD TRAINS 的产品线级关税数据（含从价等值 AVE）。每个观测为某报告经济体在某一年，其数值为该年所有 HS 产品线适用关税的算术平均。

该指标是衡量一国整体关税保护水平的标准变量，可用于贸易保护主义与供应链风险分析。