Earnings for the Federal Government’s mining tax have again been revised down, with the latest figures predicting it will only raise $800 million.
The new figures from the Parliamentary Budget Office show the tax is now expected to deliver less than half of the government’s forecast announced at the end of last year.
Just 12 months ago the Gillard government predicted the mining tax would raise $3 billion this financial year.
The ABC reported the forecasted revenue fall to $800 million is a trend expected to continue over the next four years.
The latest revenue figures have prompted the Greens to call from the profits based mining tax to be rewritten.
Greens leader Christine Milne attributes a fall in commodity prices and "flaws" with the design of the tax for the revenue drop.
"It's hard to believe that the Government has been through all this pain with the mining tax and when push comes to shove so little is being raised," she said.
"If you actually increase the rate at which the tax will be paid, plug the loopholes, include gold, you can still raise $26.2 billion over the forward estimates.
"The Prime Minister is staring down a defeat at this election.
"Why wouldn't she now say that yes, there were major flaws in the mining tax, yes the big mining companies are making a fortune, yes we can expect them to run a campaign – but look how much they have pocketed and look how little they are paying."
Minerals Council head Mitch Hooke said he is not surprised by the forecast slump.
"The exchange rate is high, commodity prices have come off, costs have doubled, and productivity's come back a third. It's no wonder that the industry is under stress," he said.
The Greens’ latest push for a tax overhaul has angered Hooke.
"The Greens position, well you know I'm getting a bit jack of this. You can't get tax out of profits if the profits aren't there. It's really quite a simple concept," he said.
The Liberal party has said if it wins the September election it will scrap the mining tax along with most of the associated spending commitments.
Warning against adopting the Greens’ plans to expand the mining tax’s scope, Liberal Senator Mathias Cormann said the tax has been a complete mess.
"The Greens want to close down the mining industry," he said.
"But once the Greens have got their way, no amount of tax targeting the mining industry will raise any money whatsoever. They don't have the best interest of the mining industry at heart."
The Government has not commented on the latest figures, saying the details will be revealed on May 14, when the budget is announced.