Tariff Rates, Tariff Revenue, and Tariff Reform: Some New Facts
比较牙买加、肯尼亚和巴基斯坦的法定关税率与实收关税率，发现两者关系微弱、非线性，且实收税率随法定税率上升而增长缓慢，对发展中国家关税改革有启示。
This article compares the statutory ad valorem tariff rates (official rates) with the ratio of tariff revenues to import values (collected rates) for Jamaica, Kenya, and Pakistan. It identifies four general features of the tariff codes, considers whether these features apply to all developing countries, and discusses four implications of these features for tariff reform. First, the collected rate for any given item in the tariff code is only weakly related to the official rate for that item. Second, the variation of collected rates around the official rate increases with the level of the official rate. Third, the collected rates, on average, increase much less than the official rates. Fourth, the relation between official rates and collected rates is nonlinear, because the slope is lower at higher levels of the official rate.