(a) a practice was, or is, generally prevalent regarding levy of cess (including non-levy thereof) on any supply of goods or services or both; and

Provided that no such cess shall be leviable on supplies made by a taxable person who has decided to opt for composition levy under section 10 of the Central Goods and Services Tax Act.

(a) the projected revenue for any financial year during the transition period, which could have accrued to a State in the absence of the goods and services tax, shall be calculated as per section 6;

The projected revenue for any year in a State shall be calculated by applying the projected growth rate over the base year revenue of that State.