We aim to be completely transparent in our approach to measuring our value and are clear about the amount of credit we may claim.

Our accounting approach is built upon three transparency principles.


We are clear whether the contribution we are stating is direct, indirect or enabled. To help us understand and report on who is responsible for what, we group activities under three headings:

  • direct activity (carried out by ourselves),
  • indirect activity (commissioned by us and carried out by our supply chain), and
  • enabled activity (enabled by us through the leasing of our land and property and carried out by others).


We are clear about our assumptions and say how confident we are in our data.

It is not practical, or even possible in some cases, to capture primary data for every indicator, so we use recognised methodologies, models and research to estimate results where necessary. We make our data sources clear in all cases.

Net contribution

We capture both negative and positive impacts from the activities across our portfolio to report a net contribution, as far as is possible.