A spending level of 35% would require an uncompromising drive for value for money in public services.

A few years ago, that spending level was higher.

But with an ageing population, if so many working people are net recipients rather than contributors to the state, public spending levels are unsustainable.

However, he added that the credit crunch has so far had little effect on spending levels.

The overall public spending level for the program, unprecedented at the time, was $4.8 billion ($76 billion in 2008 dollars), and helped to stimulate the economy through public works projects.