Overview of Calculation Methodologies for Metric Definitions in the Scope 3 DashboardThe Scope 3 dashboard provides a comprehensive view of emissions across various categories. This article outlines the methodologies used to calculate the different metric definitions, categorised into Scripted, Manual, and Calculated Metrics. Metric Definitions used in Scope 3 dashboard Scripted Metric Definitions: Emissions by Supplier Category: Using Supplier Emission Factor (Entities - Supplier Categories)Using LCA Emission Value (Entities - Supplier Categories)Using EEIO Emission Factor (Entities - Supplier Categories) Emissions by Spend Category: Using EEIO Emission Factor (Entities - Spend Categories) Emissions by GHG Category: Using Supplier Emission Factor (Entities - GHG Categories)Using LCA Emission Value (Entities - GHG Categories)Using EEIO Emission Factor (Entities - GHG Categories) Manual Metric Definitions: Suppliers with SBTi Approved Targets: (Entities - Suppliers) Suppliers Who Responded to CDP: (Entities - Suppliers) Calculated Metric Definitions: Aggregated Scope 3 Emissions: Emissions by supplier category by supplier emission factor + Emissions by supplier category by EEIO emission factor + Emissions by supplier category by LCA emission value Calculation Logic Based on Category The calculations for Scope 3 emissions are conducted based on the availability of specific emission factors. The hierarchy for using these factors is LCA, Supplier Emission Factor, and EEIO Emission Factor. For a Category with LCA Emissions: Data Source: cmdb_model table where LCA is not empty.Formula: Emissions by LCA=∑(model.expected_lifetime_co2e × count of assets per model) for assets procured in the current year and in states "In stock", "In transit", "In use", and "In maintenance". Unit: kgCO2e For a Category with Supplier Emission Factor (KgCO2e/$): Data Source: cmdb_model table where LCA is empty.Formula: Emissions by Supplier Emission Factor=∑(Expenditure of all assets per model×sn_esg_scope3_supplier_emissions_by_model.supplier_emission_factor) for assets procured in the current year and in states "In stock", "In transit", "In use", and "In maintenance". Unit: kgCO2e For a Category with Supplier Emission Factor (KgCO2e/unit): Data Source: cmdb_model table where LCA is empty.Formula: Emissions by Supplier Emission Factor=∑(count of assets per model×sn_esg_scope3_supplier_emissions_by_model.supplier_emission_factor) for assets procured in the current year and in states "In stock", "In transit", "In use", and "In maintenance". Unit: kgCO2e For a Category with EEIO Emission Factor: Data Sources: Emission activity from the Scope 3 emission category types table.Emission factor from the sn_esg_emission_factor table for Carbon dioxide equivalent (All GHGs) where "from unit" is $ and "to unit" is kgCO2e for the selected emission activity in step 1.Emission factor value for the current year from the sn_esg_emission_factor_location table.cmdb_model table where both Supplier Emission Factor and LCA Emission Factor are empty. Formula: Emissions by EEIO=∑(asset_costs×eeio emission factor×inflation factor) for all models. Unit: kgCO2e The formula for transforming the current spend value to 2018 value is: P = A / (1 + IR1/100) (1 + IR2/100) (1 + IR3/100) (1 + IR4/100) (1 + IR5/100) where: A = amount spent in current year (2023)P = amount spent in year 2018IR1 = Inflation rate in current year (2023)IR2 = Inflation rate in previous year-1 (2022)IR3 = Inflation rate in previous year-2 (2021)IR4 = Inflation rate in previous year-3 (2020)IR5 = Inflation rate in previous year-4 (2019) The formula for calculating EEIO emissions using EEIO emission factors - Emissions = EF * spend in dollar in 2018 (P) where: EF = EEIO emission factorP = amount spent in year 2018 Emission Calculation Hierarchy While calculating emissions, the following hierarchy is followed: LCA Emissions: A model will be used for LCA emissions if the LCA emission factor is available. Models used for LCA emissions are excluded from Supplier and EEIO emission calculations. Supplier Emission Factor: If LCA emissions are not available, the Supplier Emission Factor is checked. Models with this factor are included in Supplier Emission calculations. EEIO Emission Factor: If neither LCA nor Supplier Emission Factors are available, the model is used for EEIO emission calculations. This hierarchy ensures that emissions are calculated accurately and avoids double-counting models across different categories.