Service Area Population (PI6686)

This metric is intended to capture the total population of the area served, whether or not the organization is providing services to all of them. Distinct from Client Individuals: Total (PI4060), this metric counts the total population in an area of coverage. For example, a water utility provider may serve an area with 45 million individuals while actively providing service to 20 million individuals, measured by Client Individuals: Total (PI4060).

Population area data may be best sourced from census records or other municipal, regional, or national records. For locations where population varies significantly at different times of the year, organizations should footnote these seasonal shifts.

This metric may help describe the WHO dimension of impact, which details which stakeholders the investment or enterprise aims to reach with the outcome. This metric may also help clarify how underserved they were prior to the investment. For more on the alignment of IRIS metrics to the five dimensions of impact, see IRIS+ and the Five Dimensions of Impact (https://iris.thegiin.org/document/iris-and-the-five-dimensions/). No single metric is sufficient to understand an impact; rather, metrics are selected as a set across all dimensions of impact. The selection of metrics to measure and describe the five dimensions should be based on best practice and evidence.