I understood what percentage of completion accounting is and know it is an absolute legitimate accounting method to account for real estate industry's revenue and cost of revenue. But the problem is as far as valuation, we have to normalize accounting bias. Obviously, percentage of completion accounting helps XIN's accounting revenue increase 50% in 2011. In the reality, the contract sales in 2011 only increased by 28% than in 2010. According to management's guidance, contract sales in 2012 is very likely to be even less than that in 2011. When apply contract sales and industry wise gross margin, the forward PE for XIN is not as attractive as the GAAP PE.