a tax on imports evaluated as a percentage of the value of the import.
a fixed percentage of the value of the good that is being imported
a tariff calculated as a percentage of the value of the goods when clearing customs
A tariff assessed as a percentage of the value of an import.
A tariff calculated "according to value," or as a percentage of the value of goods cleared through customs; for example, 10% ad valorem means 10% percent of the value of the entered merchandise