Aggregation Handbook

Understand how GRESB aggregates asset-level performance metrics.

Introduction

The GRESB Real Estate Assessment requires Participants to report on Energy, GHG, Water, and Waste performance at the asset level. This page explains how GRESB aggregates asset-level performance metrics to the portfolio level.

Note that the aggregation calculations covered in this page differ from those made to aggregate asset-level scores. To understand how GRESB aggregates asset-level scores, please refer to the Score Contribution guidance.

1

Data Coverage

GRESB evaluates data coverage through two dimensions: area and time.

• Data Coverage (area) refers to the amount of space (expressed as % of the maximum space) covered by performance data points.

• Data Coverage (time) refers to the amount of time (expressed as % of the ownership period) covered by performance data points.

Data Coverage (Area)

This section describes GRESB's methodology for calculating Data Coverage (area) for energy per control type (tenant vs. landlord). The same methodology applies to water (simpler since GRESB recognizes only one water type).

Data Coverage (area) per subspace is calculated by dividing the sum of each energy type’s Floor Area Covered by the sum of its corresponding Maximum Floor Area. The same calculation is performed for both control types: Landlord Controlled and Tenant Controlled.

Energy can be reported either at Whole Building or Base Building + Tenant Space level. Each level corresponds to a control type:

Whole Building level:

• Whole Building → Landlord Controlled (WB LC)

• Whole Building → Tenant Controlled (WB TC)

Base Building + Tenant Space level:

• Common Areas → Landlord Controlled (CA)

• Shared Services → Landlord Controlled (SS)

• Tenant Space - Landlord Controlled → Landlord Controlled (TS LC)

• Tenant Space - Tenant Controlled → Tenant Controlled (TS TC)

If an asset is reported at the Whole Building level, its Data Coverage (Area) equals the Data Coverage (Area) of the Whole Building area. If an asset is reported at the Base Building + Tenant Space level, each individual subspace corresponding to the same control type is aggregated to calculate the Data Coverage (Area) for that control type.

Landlord Controlled

Landlord Controlled areas include: WB LC, CA, SS and TS LC. The Data Coverage (area) of a specific subspace is calculated as the sum of each energy type’s Floor Area Covered divided by the sum of its corresponding Maximum Floor Area.

Example: Whole Building - Landlord Controlled

$$\text{Data Coverage (Area)}_{wb,lc} = \frac{ \sum_{j=1}^{n} \text{Floor Area Covered}_{wb,lc,j} }{ \sum_{j=1}^{n} \text{Maximum Floor Area}_{wb,lc,j} }$$

Formula 1.a. Data Coverage (Area) - Whole Building - Landlord Controlled

Where:

wb	Whole Building
lc	Landlord Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
n	Total number of applicable energy types

Note: Lowercase subscripts refer to asset-level metrics, while capital letters refer to property sub-type-level metrics.

Since the Whole Building level represents the entire asset, the Whole Building Data Coverage (Area) equals the asset’s Data Coverage (Area).

$$\text{Data Coverage (Area)}_{lc} = \text{Data Coverage (Area)}_{wb,lc}$$

Formula 1.b. Data Coverage (Area) at the asset level - Landlord Controlled

For assets reported at the Base Building + Tenant Space level, the Data Coverage (Area) for Landlord Control is calculated as the weighted-average sum of the Data Coverage (Area) of each subspace classified as Landlord Controlled, using the corresponding Area Size as weighting factor:

$$\text{Data Coverage (Area)}_{lc} = \frac{ \sum_{lc} \left( \frac{ \sum_{j=1}^{n} \text{Floor Area Covered}_{lc,j} }{ \sum_{j=1}^{n} \text{Maximum Floor Area}_{lc,j} } \times \text{Area Size}_{lc} \right) }{ \sum_{lc} \text{Area Size}_{lc} }$$

Formula 2. Data Coverage (Area) - Base Building + Tenant Spaces Landlord Controlled

Where:

lc	Landlord Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
n	Total number of applicable energy types

To aggregate Landlord Controlled Data Coverage (Area) from the asset level to the property sub-type and country level, GRESB applies a weighted average using the corresponding Landlord Controlled floor area of an asset as the weighting factor. The percentage of ownership the reporting entity holds in an asset is taken into account when calculating the corresponding Landlord Controlled (LC) floor area weight.

For assets reported at the Base Building + Tenant Space level, the following assumptions apply:

• Tenant Spaces - Landlord Controlled and Tenant Spaces - Tenant Controlled do not overlap.

• The Shared Services floor area overlaps with all other subspaces.

Therefore, the Landlord Controlled (LC) weight is calculated as:

$$\text{LC Weight} = \frac{ \max\!\left(CA + TS_{LC},\, SS\right) }{ \max\!\left(CA + TS_{LC},\, SS\right) + TS_{TC} } \times \text{Asset Size} \times \% \text{ of Ownership}$$

Formula 3. Landlord Controlled weight - Base Building and Tenant Spaces

Finally, GRESB calculates Data Coverage (Area) at the property sub-type and country level for a specific control type (Landlord Controlled) as a weighted average of asset-level Data Coverage (Area) of the same control type, using the LC weights as weighting factors.

$$\text{Data coverage (Area)}_{P,C,LC} = \frac{ \sum_{i=1}^{n} \left( \text{Data coverage (area)}_{lc,i} \times \text{LC Weight}_{i} \right) }{ \sum_{i=1}^{n} \text{LC Weight}_{i} }$$

Formula 4. Data Coverage (Area) at property sub-type & country level - Landlord Controlled

Where:

Data Coverage (Area) lc, i	Represents the Data Coverage (Area) corresponding to the Landlord Controlled areas of asset i
LC Weight	Landlord Controlled weight of asset i
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country
lc	Landlord Controlled

Note: For assets reporting at the Whole Building level, the LC Weight equals the Asset Size multiplied by the % of Ownership of the corresponding asset.

Tenant Controlled

Tenant Controlled areas consist of WB TC and TS TC. The Data Coverage (Area) of a specific subspace is calculated by dividing the sum of each energy type’s Floor Area Covered by the sum of their corresponding Maximum Floor Area.

Example: Whole Building - Tenant Controlled

$$\text{Data Coverage (Area)}_{wb,tc} = \frac{ \sum_{j=1}^{n} \text{Floor Area Covered}_{wb,tc,j} }{ \sum_{j=1}^{n} \text{Maximum Floor Area}_{wb,tc,j} }$$

Formula 5.a. Data Coverage (Area) - Whole Building - Tenant Controlled

Where:

wb	Whole Building
tc	Tenant Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
n	Total number of applicable energy types

Since the Whole Building level represents the entire asset, the Whole Building Data Coverage (Area) equals the asset’s Data Coverage (Area).

$$\text{Data Coverage (Area)}_{tc} = \text{Data Coverage (Area)}_{wb,tc}$$

Formula 5.b. Data Coverage (Area) - Tenant Controlled

For assets reported at the Base Building + Tenant Space level, the Data Coverage (Area) for Tenant Control equals the Data Coverage (Area) of the subspace TS TC. The same calculation methodology as Formula 5.a applies:

$$\text{Data Coverage (Area)}_{tc} = \frac{ \sum_{j=1}^{n} \text{Floor Area Covered}_{tc,j} }{ \sum_{j=1}^{n} \text{Maximum Floor Area}_{tc,j} }$$

Formula 5.c. Data Coverage (Area) - Base Building + Tenant Spaces Tenant Controlled

Where:

tc	Tenant Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
n	Total number of applicable energy types

To aggregate Tenant Controlled Data Coverage (Area) from the asset level to property sub-type and country level, GRESB applies a weighted average using the corresponding Tenant Controlled floor area of an asset as the weighting factor. The percentage of ownership the reporting entity has in an asset is factored in when calculating the corresponding Tenant Controlled (TC) floor area weight.

For assets reported at the Base Building + Tenant Space level, the following assumptions apply:

• Tenant Spaces - Landlord Controlled and Tenant Spaces - Tenant Controlled don't overlap.

• The Shared Services floor area overlaps with all other subspaces.

Therefore, the Tenant Controlled (TC) weight is calculated using:

$$\text{TC Weight} = \frac{ TS_{TC} }{ \max\!\left(CA + TS_{LC},\, SS\right) + TS_{TC} } \times \text{Asset Size} \times \% \text{ of Ownership}$$

Formula 6.a. Tenant controlled weight - Base Building and Tenant Spaces

Alternatively:

$$\text{TC Weight} = \text{Asset Size} \times \% \text{ of Ownership} - \text{LC Weight}$$

Formula 6.b. Tenant controlled weight - Base Building and Tenant Spaces

Finally, GRESB calculates Data Coverage (Area) at property sub-type and country level for a specific control type (Tenant Controlled) as a weighted average of asset-level Data Coverage (Area) of the same control type, using TC weights as weighting factors:

$$\text{Data Coverage (Area)}_{P,C,TC} = \frac{ \sum_{i=1}^{n} \left( \text{Data Coverage (Area)}_{tc,i} \times \text{TC Weight}_{i} \right) }{ \sum_{i=1}^{n} \text{TC Weight}_{i} }$$

Formula 7. Data Coverage (Area) at property sub-type & country level - Tenant Controlled

Note: For assets reported at the Whole Building level, the TC Weight equals the Asset Size multiplied by the % of Ownership of the corresponding asset.

Where:

Data Coverage (Area) tc, i	Represents the Data Coverage (Area) corresponding to the Tenant Controlled areas of asset i
TC Weight	Tenant Controlled weight of asset i
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country

Data Coverage (Time) | Data Availability

This section outlines the methodology used by GRESB to calculate Data Coverage (Time) for Energy, GHG, and Water.

Data Coverage (Time) of an asset is calculated based on:

• Ownership Period: the period during which an asset is owned by the reporting entity. GRESB expects participants to report performance data for the entire Ownership Period during which the asset is classified as a Standing Investment.

• Status: GRESB participants are not required to report performance data for periods when an asset is classified as New Construction and/or Major Renovation. GRESB requires data reporting for periods when an asset is classified as a Standing Investment. As a result, aggregation and scoring calculations only consider the portion of the ownership period during which the asset is classified as a Standing Investment. Periods classified as New Construction or Major Renovation are excluded from aggregation weighting.

Data Coverage (Time) of an asset is calculated as:

$$\text{Data Coverage (Time)} = \frac{ \text{Data Availability (To)} - \text{Data Availability (From)} }{ \text{Ownership Period}_{SI} }$$

Formula 8. Data Coverage (Time) at the asset level

Where:

Data Availability (To)	Data Availability End Date of an asset
Data Availability (From)	Data Availability Start Date of an asset
Ownership Period si	Ownership Period for which the asset was a Standing Investment

Note: If a participant collects performance data from before the acquisition date, they may report a Data Availability period that exceeds the Ownership Period. In this case, Ownership Period_si will be the maximum between Data Availability (To) - Data Availability (From) and Ownership Period_si.

GRESB calculates Data Coverage (Time) at property sub-type and country level as a weighted average of asset-level Data Coverage (Time), using Ownership Period_SI as weighting factors.

$$\text{Data coverage (Time)}_{P,C} = \frac{ \sum_{i=1}^{n} \left( \text{Data coverage (Time)}_{i} \times \text{Ownership Period}_{SI,i} \right) }{ \sum_{i=1}^{n} \text{Ownership Period}_{SI,i} }$$

Formula 9. Data Coverage (Time) at property sub-type and country level

Where:

Data Coverage (Time)	Data Coverage (Time) of asset i
Ownership Period si	Ownership Period for which the asset was a Standing Investment
P	Specific property sub-type
C	Specific country
i	An asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country

Note: Data Availability can be greater than Ownership Period_SI if the participant has collected performance data prior to the acquisition date. In this case, Ownership Period_SI will be the maximum between Data Availability (To) - Data Availability (From) and Ownership Period_SI.

Data Coverage (Area/Time)

This section outlines GRESB methodology to aggregate the two dimensions of Data Coverage: Area and Time. The Data Coverage (Area/Time) metric is calculated per control type (Landlord Controlled and Tenant Controlled).

Firstly, GRESB calculates Data Coverage (Area/Time) at the asset level as the product of Data Coverage (Area) and Data Coverage (Time).

Landlord Controlled:

$$\text{Landlord Controlled: } \text{Data Coverage (Area/Time)}_{lc} = \text{Data Coverage (Area)}_{lc} \times \text{Data coverage (Time)}$$

Formula 10.a. Data Coverage (Area/Time) - Landlord Controlled at the asset level

Where:

Data Coverage (Area) lc	Data Coverage (Area) at the asset level for Landlord Controlled
Data Coverage (Time)	Data Coverage (Time) at the asset level
lc	Landlord Controlled

Tenant Controlled:

$$\text{Tenant Controlled: } \text{Data Coverage (Area/Time)}_{tc} = \text{Data Coverage (Area)}_{tc} \times \text{Data coverage (Time)}$$

Formula 10.b. Data Coverage (Area/Time) - Tenant Controlled at the asset level

Where:

Data Coverage (Area) tc	Data Coverage (Area) at the asset level for Tenant Controlled
Data Coverage (Time)	Data Coverage (Time) at the asset level
tc	Tenant Controlled

GRESB calculates Data Coverage (Area/Time) at the property sub-type and country level for a specific control type as a weighted average of asset-level Data Coverage (Area/Time), using (TC Weight × Ownership Period_SI) or (LC Weight × Ownership Period_SI) as weighting factors.

This weighting factor accounts for both the control-specific weight (LC Weight and TC Weight) and the period of ownership (Ownership Period_SI).

Landlord Controlled:

$$\text{Data Coverage (Area/Time)}_{P,C,LC} = \frac{ \sum_{i=1}^{n} \left( \text{Data Coverage (Area/Time)}_{lc,i} \times \text{LC Weight}_{i} \times \text{Ownership Period}_{si,i} \right) }{ \sum_{i=1}^{n} \left( \text{LC Weight}_{i} \times \text{Ownership Period}_{si,i} \right) }$$

Formula 11.a. Data Coverage (Area/Time) - Landlord Controlled at property sub-type & country level

Where:

Data Coverage (Area/Time) lc,i	Data Coverage (Area/Time) - Landlord Controlled of asset i
LC Weight	Landlord Controlled weight of asset i
Ownership PeriodSI	Ownership Period for which the asset was a Standing Investment
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type and country
n	Total number of assets in a specific property sub-type and country

Tenant Controlled:

$$\text{Data Coverage (Area/Time)}_{P,C,TC} = \frac{ \sum_{i=1}^{n} \left( \text{Data Coverage (Area/Time)}_{tc,i} \times \text{TC Weight}_{i} \times \text{Ownership Period}_{si,i} \right) }{ \sum_{i=1}^{n} \left( \text{TC Weight}_{i} \times \text{Ownership Period}_{si,i} \right) }$$

Formula 11.b. Data Coverage (Area/Time) - Tenant Controlled at property sub-type and country level

Where:

Data Coverage (Area/Time) tc,i	Data Coverage (Area/Time) - Tenant Controlled of asset i
TC Weight	Tenant Controlled weight of asset i
Ownership PeriodSI	Ownership Period for which the asset was a Standing Investment
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type and country
n	Total number of assets in a specific property sub-type and country

Note: Data Availability can be greater than Ownership Period_SI if the participant collects performance data prior to acquisition. In this case, Ownership Period_SI will be the maximum between Data Availability (To) - Data Availability (From) and Ownership Period_SI.

2

Like-for-Like

This section outlines the methodology used by GRESB to aggregate the Like-for-Like (LFL) Change and the Like-for-Like Data Availability from asset level to property sub-type and country level.

Like-for-Like (LFL) only includes comparable data points from two consecutive reporting periods. To be eligible for inclusion in LFL calculations, assets must meet all of the following criteria, for both the current and previous reporting years:

• Data Availability covers the full year (> 355 days);

• Data Coverage is positive;

• Data Coverage is the same (within 1% error threshold);

• The asset is classified as Standing Investment.

Note: To avoid infinite values, Like-for-Like also requires the existence of a positive performance value in the previous year.

Like-for-Like Change

LFL Change calculates the percentage change in consumption/emission from last year (LY) to current year (CY). This metric is calculated per control type (Landlord Controlled and Tenant Controlled).

GRESB calculates LFL Change at the property sub-type and country level for a specific control type as the sum of asset-level LFL Change corresponding to that control type, using LY consumption as weighting factors. Both LY and CY consumption are weighted by the percentage of ownership the reporting entity has in each asset.

Energy - Landlord Controlled:

$$\text{LFL Change}_{P,C,LC} = \frac{ \sum_{i=1}^{n} \left( CY\ \text{consumption}_{lc,i} \times \% \text{ of Ownership} - LY\ \text{consumption}_{lc,i} \times \% \text{ of Ownership} \right)_{i} }{ \sum_{i=1}^{n} \left( LY\ \text{consumption}_{lc,i} \times \% \text{ of Ownership} \right)_{i} }$$

Formula 12.a. LFL Change at property sub-type & country level - Landlord Controlled

Where:

lc	Landlord Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country
% Ownership	Percentage of the asset owned by the reporting entity

Energy - Tenant Controlled:

$$\text{LFL Change}_{P,C,TC} = \frac{ \sum_{i=1}^{n} \left( CY\ \text{consumption}_{tc,i} \times \% \text{ of Ownership} - LY\ \text{consumption}_{tc,i} \times \% \text{ of Ownership} \right)_{i} }{ \sum_{i=1}^{n} \left( LY\ \text{consumption}_{tc,i} \times \% \text{ of Ownership} \right)_{i} }$$

Formula 12.b. LFL Change at property sub-type & country level - Tenant Controlled

Where:

tc	Tenant Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country
% Ownership	Percentage of the asset owned by the reporting entity

Note: Outdoor/Exterior Areas/Parking consumption are included in the scope of the LFL Change and are differentiated by control type.

The same methodology applies to GHG (with LFL Change calculated per scopes: Scopes 1/2 and Scope 3) and to Water (GRESB recognizes only one type of Water consumption).

Examples (descriptive):

Example 1

Asset A reported electricity consumption in both years, and CY consumption is 0.

Assuming the asset is a Standing Investment and has data availability > 355 days, LY consumption is positive, and data coverages are positive and stable, the Electricity consumption of Common Areas is included in the LFL Change scope.

Example 2

Same scenario but LY electricity consumption is 0. However, Asset B has positive LY fuels consumption.

Since there is positive LY consumption in the Common Areas, both LY and CY consumption are included in the LFL Change calculation.

Example 3

Asset C reported electricity consumption equal to 0 for LY, but CY consumption is positive.

The consumption for both years will not be included in the LFL Change, as LY consumption in the Common Areas is equal to 0.

Like-For-Like Data Availability

LFL Data Availability is calculated similarly to Data Coverage (Area). This metric is calculated per control type (Landlord Controlled and Tenant Controlled) using the same methodology. In addition to the criteria above, calculating LFL Data Availability requires positive LY consumption/emission within a subspace of an asset.

Energy - Landlord Controlled:

$$\text{LFL Data Availability}_{lc} = \frac{ \sum_{lc} \left( \frac{ \sum_{j=1}^{n} \text{Floor Area Covered}_{lc,j} }{ \sum_{j=1}^{n} \text{Maximum Floor Area}_{lc,j} } \times \text{Area Size}_{lc} \right) }{ \sum_{lc} \text{Area Size}_{lc} }$$

Formula 13.a. LFL Data Availability at asset level - Landlord Controlled

Where:

lc	Landlord Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
n	Total number of applicable energy types

$$\text{LFL Data Availability}_{P,C,LC} = \frac{ \sum_{i=1}^{n} \left( \text{LFL Data Availability}_{lc,i} \times \text{LC Weight}_{i} \right) }{ \sum_{i=1}^{n} \text{LC Weight}_{i} }$$

Formula 14.a. LFL Data Availability at property sub-type & country level - Landlord Controlled

Where:

LFL Data Availability_lc,i	LFL Data Availability - Landlord Controlled of asset i
LC Weight	Landlord Controlled weight of asset i
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country

Energy - Tenant Controlled:

$$\text{LFL Data Availability}_{P,C,TC} = \frac{ \sum_{i=1}^{n} \left( \text{LFL Data Availability}_{tc,i} \times \text{TC Weight}_{i} \right) }{ \sum_{i=1}^{n} \text{TC Weight}_{i} }$$

Formula 13.b. LFL Data Availability at asset level - Tenant Controlled

Where:

tc	Tenant Controlled
j	Represents an energy type (Fuel, Electricity, District Heating and Cooling)
n	Total number of applicable energy types

$$\text{LFL Data Availability}_{P,C,TC} = \frac{ \sum_{i=1}^{n} \left( \text{LFL Data Availability}_{tc,i} \times \text{TC Weight}_{i} \right) }{ \sum_{i=1}^{n} \text{TC Weight}_{i} }$$

Formula 14.b. LFL Data Availability at property sub-type and country level - Tenant Controlled

Where:

LFL Data Availability_tc,i	LFL Data Availability - Tenant Controlled of asset i
TC Weight	Tenant Controlled weight of asset i
P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country

Note: Floor Area Covered and Maximum Floor Area values should only be included in the formulas above if the subspace is eligible for LFL Data Availability.

3

Intensities

This section outlines GRESB's methodology for calculating average Energy/GHG/Water Intensities from asset level to property sub-type and country level.

Intensities are calculated for assets that meet the following criteria:

• Are classified as Standing Investments

• Have a full year (>=355 days) of data availability

• Have vacancy rate lower than 20%

• Have Data Coverage (Area/time) of 75% or more

GRESB calculates equity-weighted intensities at the asset level and aggregates them to the property sub-type and country level. This is done by dividing the sum of an asset’s total consumption/emissions by the sum of the asset sizes (GFA), weighted by the percentage of ownership the reporting entity has in each asset. When data coverage ranges between 75% and 100%, GRESB linearly extrapolates consumption/emissions to 100% to ensure data completeness.

Assets that don't meet the criteria are excluded from the calculations.

Energy Intensity

$$\text{Intensity}_{P,C,\text{Energy}} = \frac{ \sum_{i=1}^{n} \left( \% \text{ ownership}_{i} \times \text{Total Energy Consumption}_{i} \right) }{ \sum_{i=1}^{n} \left( \% \text{ ownership}_{i} \times \text{Asset Size (GFA)}_{i} \times \text{Data Coverage (Area/Time)}_{i} \right) }$$

Formula 15. Average Energy Intensity per property sub-type & country level

Where:

P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country

GHG Intensity

$$\text{Intensity}_{P,C,\text{GHG}} = \frac{ \sum_{i=1}^{n} \left( \% \text{ ownership}_{i} \times \text{Total GHG Emissions}_{i} \right) }{ \sum_{i=1}^{n} \left( \% \text{ ownership}_{i} \times \text{Asset Size (GFA)}_{i} \times \text{Data Coverage (Area/Time)}_{i} \right) }$$

Formula 16. Average GHG Intensity per property sub-type & country level

Where:

P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country

Water intensity

$$\text{Intensity}_{P,C,\text{Water}} = \frac{ \sum_{i=1}^{n} \left( \% \text{ ownership}_{i} \times \text{Total Water Consumption}_{i} \right) }{ \sum_{i=1}^{n} \left( \% \text{ ownership}_{i} \times \text{Asset Size (GFA)}_{i} \times \text{Data Coverage (Area/Time)}_{i} \right) }$$

Formula 17. Average Water Intensity per property sub-type and country level

Where:

P	Specific property sub-type
C	Specific country
i	Asset in a specific property sub-type & country
n	Total number of assets in a specific property sub-type & country

4

Outliers

Outliers are observations that lie at an abnormal distance from other values. This does not necessarily indicate incorrect reporting; participants are encouraged to review outliers to ensure accuracy.

The two most common explanations for outliers relate to vacancy rates and data availability periods:

• Intensity values are normalized by both vacancy and data availability.

• Like-for-Like values are normalized by vacancy only. LFL outliers are not normalized by data availability because an asset is only eligible for LFL inclusion if the data is available for 2 continuous years.

Like-for-Like Outliers

$$\frac{ \left( \frac{CY\ \text{consumption}}{1 - CY\ \text{vacancy rate}} \right) - \left( \frac{LY\ \text{consumption}}{1 - LY\ \text{vacancy rate}} \right) }{ \frac{LY\ \text{consumption}}{1 - LY\ \text{vacancy rate}} }$$

See here for information on outlier thresholds, impact on scoring and remediation.

Intensity Outliers

$$\frac{ CY\ \text{Consumption} }{ \text{Applicable Area} \times \text{Data Availability} \times \left(1 - CY\ \text{Vacancy Rate}\right) }$$

See here for information on outlier thresholds, impact on scoring and remediation.