The tax may be levied as a percentage of the value of the imports, which is called an AD valorem tariff.

税费可以按照进口商品价值的一定的百分比来征收，这称为从价关税。

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A compound tariff is a combination of a specific and an AD valorem tariff.

复合关税是从价税与从量税两种关税相结合所征收的关税。

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According to the revised Regulations, the amount of consumption tax payable may be calculated ad valorem, at a flat rate or by a combination of the two.

修订后的条例规定消费税实行从价定率、从量定额，或者从价定率和从量定额复合计税的办法计算应纳税额。

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Then there's a 54-cent tariff (not including a 2.5% ad valorem levy) to keep cheaper Brazilian ethanol out of the country.

FORBES: Field of Dreamers

To insulate domestic ethanol producers from competitors in Colombia and Brazil, the government imposes a 54-cent-per-gallon tariff and a 2.5 percent ad valorem tax on ethanol imports.

FORBES: Senators Back Legislation to End Ethanol Subsidy

For a period of 20 years the existing Turkish customs tariff shall remain in force throughout the whole of the blue and red areas, as well as in areas (a) and (b), and no increase in the rates of duty or conversions from ad valorem to specific rates shall be made except by agreement between the two powers.

BBC: Map detailing the Sykes-Picot agreement