Note: In addition, changes have been made to a number of data points over the years 2012-2015. When we carried out a review of our Scope 1 GHG emissions calculations in 2016 to ensure they reflected best practice and utilised the most appropriate and up-to-date factors available, we made some minor changes to the conversion factors we use from the ‘Compendium of Greenhouse Gas Emissions Methodologies for the Oil and Natural Gas Industry’ (American Petroleum Institute (API) 2009) by selecting ones that align more accurately to the fuel types we use. These changes affected the NOx, SO2 and VOCs data in addition to the GHG related air emission data so we are restating it here.