Excise duty rates on tobacco adjusted; new ad valorem and specific per-unit duties prescribed under the Fourth Schedule. The Fourth Schedule amends excise duties in the First Schedule to the Additional Duties of Excise Act by substituting new specific per-unit rates for several unmanufactured tobacco sub-items; replacing the manufactured tobacco entry for the relevant sub-item with a one hundred per cent ad valorem duty; and substituting a composite charge of an ad valorem percentage plus a specific per-square-metre amount against the identified sub-item in the other listed item.