Mr Abbott said his great fear was that the government would continue to play the class war card "even more fiercely in the future than they have in the past." Shadow treasurer Joe Hockey said the budget must include honest assumptions for both revenue and economic forecasts, particularly for growth. Mr Hockey said he would be looking at the revenue forecasts for both the carbon and mining taxes. He said the carbon tax was supposed to deliver $9.4 billion in 2015 based on a European price of $29 a tonne, when the price was trading around $5 to $6 per tonne. "The mining tax obviously is not going to raise anywhere near what was originally forecast," he said. In the first six months of the mining tax, it raised just $126 million, when it was supposed to bring in $2 billion in its first year. Mr Hockey says costs associated with asylum seekers have also blown out. He also wants to see the end of "money shuffling" in the budget, pointing to the push back to next year of some $3 billion due from spectrum licence sales. The opposition also wants to see the cost of implementing major items, such as the Gonski education funding reforms and the national disability insurance scheme. "The government can no longer fudge it by claiming to deliver the scheme then have a token amount compared to what the real cost of the scheme is in the budget," Mr Hockey said. That means going beyond the forward estimates - they need to lay down the six- to eight-year costs when it is at the full operational level. He said there must also be a strategy to stop government debt increasing. "The government has to have a plan to deliver a surplus and start to pay down the debt," he said.