Senator JOYCE (Queensland—Leader of The Nationals in the Senate) (14:50): My question is to the Minister representing the Minister for Climate Change and Energy Efficiency, Senator Wong. I refer the minister to the fact that this morning $21 billion has been wiped off the Australian Stock Exchange as concerns grow over the handling of the sovereign debt crisis in Europe and the United States. I also refer to the warnings made by the chief economist at the International Monetary Fund yesterday that the global economy has entered a dangerous new phase. Given that the overseas economic environment is fragile and could worsen further, are there any circumstances under which the government would reconsider its commitment to introduce a carbon tax on 1 July next year?