The 20th anniversary of the introduction of the GST last week gave rise to a fresh wave of calls for the consumption tax to be increased to 15 per cent, or applied more broadly to capture goods and services exempted in 2000, in the pursuit of additional revenue for state governments.

Best estimates are that lifting the rate to 15 per cent, or extending the current GST to food, health and education, would raise around $30 billion a year.