text: 1 Adjusted operating profit and adjusted net debt are Non-GAAP measures and should 
  not be considered as substitutes or alternatives for GAAP measures. They are not 
  defined terms under IFRS, and do not have a standard meaning, so may not be a 
  reliable way to compare us to other companies. See “Non-GAAP Measures” for 
  information about these measures, including how we calculate them. 