Vat on excise duty

In that method a certain percentage of RSP is deduted From RSP to arive at assessable value on which Excise is charged.. that is called abatement... this abatement is notionally assumed as all other taxes, duties and levy.. thus VAT also gets deducted by this.... Also the purpose of Excise is to Tax the value at the time of removal from factory after production.. VAT is charged later at sale, thus it is excluded