New Delhi, July 15 -- This month, India's goods and services tax (GST) completed eight years. This is a milestone reform. It is a consumption tax that unifies the national economic market, getting rid of inter-state frictions and tax cascades, and is fully electronic with in-built incentives for compliance and prevention of leakage. In the five years since 2020-21, annual gross GST collections have more than doubled to Rs.22 trillion.

This growth has generally kept pace with that of India's nominal GDP, although its promise was of higher buoyancy. It still leaves out nearly half the economy-most notably fuels, energy and electricity-from its purview. Even among the items covered, it has too many exemptions. Perhaps that explains why its ...