Annual Report 2007

Annual Report 2007 年報 91 4. Key Sources of Estimation Uncertainty (Continued) Allowance for doubtful receivables Allowance for trade receivable is made based on the evaluation of collectability and ageing analysis of accounts and on directors’ judgement by reference to the estimation of the future cash flow discounted at an effective interest rate to calculate the present value. Where the actual future cash flows are less than expected, a material impairment loss may arise. As at 31 December 2007, the carrying amount of trade receivables which are past due but considered has not been impaired is RMB14,151,000. Impairment of goodwill Determining whether goodwill is impaired requires an estimation of the value in use of the cash-generating units to which goodwill has been allocated. The value in use calculation requires the directors to estimate the future cash flows expected to arise from the cash- generating unit and a suitable discount rate in order to calculate present value. The carrying amount of goodwill at the balance sheet date was RMB12,077,000 and no impairment loss was recognised during 2007. Details of the recoverable amount calculation are disclosed in Note 16. 4. 估計不確定因素之主要來 源（續） 呆壞賬撥備 貿易應收款項撥備根據賬款可收回程度 評估及賬齡分析，按董事參考以實際利 率貼現的日後現金流量現值估計所作 判斷而定。當實際日後現金流量低於預 期，可能產生重大減值虧損。於二零零 七年十二月三十一日，已過期但視為無 減值的貿易應收款項賬面值為人民幣 14,151,000 元。 商譽減值 釐定商譽有否減值時，須估計商譽獲分 配之現金產生單位的使用價值，而計算 使用價值時，董事須估計現金產生單位 預期可產生之未來現金流量及採用合適 貼現率，以計算現值。 商 譽 於 結 算 日 的 賬 面 值 為 人 民 幣 12,077,000 元，且於二零零七年並無確認 任何減值虧損。計算可收回金額之詳情 於附註 16 披露。