共同実施
In August 2008 prices for CERS were $20 a tonne. By September 2012, prices for CERS had collapsed to below $5. This was in response to the Eurozone debt crisis reducing industrial activity and the over-allocation of emission allowances under the European Union Emissions Trading Scheme. "The Economist" described the Clean Development Mechanism as a "complete disaster in the making" and "in need of a radical overhaul". "The Guardian" also reported the prolonged downward trend in the price of CERs, which had been traded for as much as $20 (£12.50) a tonne before the global financial crisis to less than $3. In October 2012, CER prices fell to a new low of 1.36 euros a tonne on the London ICE Futures Europe exchange. In October 2012 Thomson Reuters Point Carbon calculated that the oversupply of units from the Clean Development Mechanism and Joint Implementation would be 1,400 million units for the period up to 2020. Point Carbon predicted that CER prices would to drop from €2 to 50 cents. On 12 December 2012 CER prices reached another record low of 31 cents.