a18c0902__Company_Announcement___FT_com__Factor
[Nature] The great majority of the Group's sales are denominated in US dollars, which is also the currency used for holding surplus cash, financing operations, and presenting external and internal results. Although many costs are incurred in US dollars, a significant portion are incurred in or influenced by the local currencies of the countries where the Group operates, principally the Australian dollar and Canadian dollar. The Group's normal policy is to avoid hedging of foreign exchange rates and so the Group may be adversely affected by appreciation in the value of other currencies against the US dollar, or to prolonged periods of exchange rate volatility. Currency fluctuations may negatively impact the Group's profitability and dividend payments as well as rating agency metrics and asset carrying values. [Factor] 
Rio Tinto is exposed to fluctuations in exchange rates
Annual Financial Report – Company Announcement - FT.com
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