The following table is our best endeavour to set a robust baseline for our UK and US operations. We have only used data from years where it has been both published and verified, either in a National Grid or predecessor company's Annual Report and Accounts, corporate responsibility / environmental reports, or as part of regulatory reporting.
Data is shown as either Scope 1 or Scope 2 in line with the World Resources Institute Greenhouse Gas Protocol Initiative.
Approximately 95% of our baseline emissions for 2010/11 are based on data traceable back to1990/01.
Restating our baseline
Where our business changes, such as the sale of National Grid Wireless in 2007 or the acquisition of KeySpan the same year, we adjust the baseline to ensure a fair comparison can be made with our current emissions .
There has been no change to our baseline between 2008/09 and 2009/10 or 2009/10 and 2010/11.
Baseline update: 2008/09 and 2007/08