text: *Expenditure Derivatives*
  We use foreign currency forward contracts (Expenditure Derivatives) to 
  hedge the foreign exchange risk on the notional amount of certain 
  forecasted expenditures. We use Expenditure Derivatives for 
  risk- 
  management purposes only. 
  
  The fair values of each of our public debt instruments are based on the 
  year-end trading values. We determine the fair values of our Debt 
  Derivatives and Expenditure Derivatives (Derivatives) using an estimated 
  credit-adjusted mark-to-market valuation by discounting cash flows to 
  the measurement date. In the case of Derivatives in an asset position, 
  the credit spread for the financial institution counterparty is added to 
  the risk-free discount rate to determine the estimated credit-adjusted 
  value for each derivative. For Derivatives in a liability position, our credit 
  spread is added to the risk-free discount rate for each derivative. 
  In 2013, we entered into an additional US $955 million of Expenditure 
  Derivatives maturing from April 2013 through December 2014, at an 
  average rate of $1.0341/US $1. As at December 31, 2013, we had a 
  total of US $900 million ($923 million) of Expenditure Derivatives for 
  our forecasted US dollar denominated expenditures at an average rate 
  for 
  of $1.0262/US $1 which have been designated as hedges 
  accounting purposes. We record changes in fair value of 
  these 
  Expenditure Derivatives in other comprehensive income. Once the 