oecd urges australia to boost mining tax, page-9

I think the tax has merit for true economic profits....the tax as promoted by Swan, Ken Henry etc kicked in at any return above the bond rate, clearly this was ridiculous.

If instead they had applied the tax at returns say 10% or more above the bond rate it would have been a lot more reasonable, and sensible. The revenues should have been siphoned into a sovereign wealth fund run independently of the government.

This was just an ill conceived concept used to paper over big holes in the budget.