Revenue recognition on construction contracts — The Group conducts a signifi cant portion of its business under construction contracts with customers, for example within aerospace related governmental programmes. The Group generally accounts for construction projects using the PoC method, recognising revenue as performance on a contract progresses measured either on a milestone or on a cost-to-cost basis depending on contract terms. This method places considerable importance on accurate estimates at completion as well as on the extent of progress towards completion. For the determination of the progress of the construction contract signifi cant estimates include total contract
costs, remaining costs to completion, total contract revenues, contract risks and other judgment s. The Management of the operating Divisions continually review all estimates involved in such construction contracts and adjusts them as necessary. See Note 19 “Trade receivables” for further information.