Australia's 'carbon budget black hole': fact or political fiction?

Discussion of the federal budget has featured much doom-mongering. This is exemplified by forecasts of a A$6-8 billion black hole in 2015-16, when the carbon tax switches to an emissions trading scheme linked with Europe. The government estimates revenue will be A$2.5 billion lower than previously forecast, thanks to revised projections for European carbon prices included in the forward estimates.