Concept of inverted duty structure in Customs is a myth

The logic of inverted duty structure is not correct. What is more relevant is the Effective Rate of Protection

The discussion on inverted duty structure has once again assumed importance because in the Budget 2018-19 there is a mention in the Annexure-VI to Part B of the Budget Speech that certain duties on some medical devices have been reduced from 2.5% to nil which is because of the need to correct inversion in the rate of duty. So the issue that we are now discussing here is whether there is any validity in the concept of inverted duty structure, or it is a myth.

The concept means that the rate of duty on raw materials and intermediates (input) must be