Valuation Problems The fact that so many different products are traded creates valuation problems, especially since new products are coming on the market all the time and must be classified within existing tariff categories. It is easy (by accident or intention) to misclassify a product and its corresponding tariff. Administering more than 13,000 categories of products means a customs agent must use professional discretion to determine, say, if silicon chips should be considered “integrated circuits for computers” or “a form of chemical silicon.” In our opening case, we saw the controversy of whether the Vietnamese fish are catfish or whether they are basa, tra, or pangasius. The classification becomes even more complex as both U.S. and Vietnamese scientists develop fish hybrids that combine, for example, fast-growing with good-tasting fish. The differences among products in tariff schedules are also minute. For example, the United States has a different tariff on athletic footwear than on sports footwear, and these are further categorized by whether the sole overlaps the upper part of the shoe or not. Each type of accessory and reinforcement of the shoes’ uppers has a different tariff.