At the highest point on the scale the Tariff indicates an ad valorem rate of duty only.

The law replaced most ad valorem rates with specific duties assessed on a good-by-good basis.

If the ad valorem rate is less than the minimum then the MIN stated in the Tariff applies.

As a starting point, he accepted the nullifiers' offer of a transition period but extended it from seven and a half years to nine years with a final target of a 20% ad valorem rate.

The Walker Tariff produced the nation's first standardized tariff: rather than setting fixed rates for specific items on a case-by-case basis, it established general schedules into which all goods could be classified, subject to defined ad valorem rates.