By Ashley Mutasa from the IMM team

From Data Points to Impact: Reflections on Portfolio-Level Aggregation

Lessons from Aggregating Impact Metrics
 I’ve always been drawn to numbers and the truths they can reveal about people and the world around us. In university, I studied neuroscience and became fascinated by how data could reveal patterns in the brain and by extension, in human behavior. That curiosity led me to study statistics, where I learned how to work with data more intentionally. Later, working in data analytics, I began to understand how numbers could drive real-world decisions. But it wasn’t until I joined Rally Assets that I had the opportunity to use data to not just explain the world, but to help change it, especially when it comes to improving people’s lives. 

As a Senior Associate on the Impact Measurement and Management team, I spend a lot of time working on something that sounds deceptively simple: aggregating impact metrics across diverse investments. Think of it as trying to combine dozens of jigsaw puzzles, each made by a different company, with different priorities, into one coherent picture. 

So Why Do We Aggregate Impact Data?
Because clients and investors don’t just want anecdotes. They want a holistic view. They want to know: What is the collective impact of my portfolio? How are we improving access to health care, clean energy, or affordable housing year over year? Aggregation helps us move from individual data points to credible, portfolio-level insights that inform decisions, strategies and likely future investments. 

But the road to aggregation isn’t always smooth. 

Challenge #1: Defining KPIs When Everyone Speaks a Different Language 

 Right now, I’m finalizing our KPI definitions and harmonizing them across recognized frameworks such as IRIS+, the ICMA Harmonized Framework for Impact Reporting and the ISSB. It’s not just about ticking boxes; it’s about understanding nuances. For example, what one organization calls “access to health care” could mean telemedicine consultations, while another means hospital beds added in rural areas. To effectively align and aggregate, we need to define the boundaries of each KPI, clearly and carefully. This precision enables us to assess to what extent we are improving access to health care, despite a diversity of innovations being pursued, each with a different metric. 

Challenge #2: Navigating Exclusions, Assumptions, and Flexible Frameworks 

 Sometimes metrics don’t quite fit the mold. That’s where exclusions come in. We’ve been building a flexible reporting framework that flags outliers, avoids double counting, and ensures we’re not forcing incompatible metrics into a single pot. We’ve asked questions like: Is it reasonable to convert the number of households into the number of people served (e.g., one family = three individuals) for the purpose of aggregation? Is that conversion material enough to influence a report user’s decision-making?  

These aren’t just technical questions, they’re ethical ones. They influence how impact is measured, interpreted and communicated. It’s also important to recognize that key assumptions underpin many of our measurements, whether estimating how many emissions were generated or avoided, or calculating profits within financial accounting.

These assumptions must be thoughtfully considered and transparently disclosed to our clients whenever they are material enough to impact decision-making. Without this transparency, the integrity and usefulness of the measurement system are significantly diminished. 

Challenge #3: The Reality of Quality Control
As anyone who has wrestled with Excel at 11 p.m can tell you, data cleaning isn’t glamorous but it’s crucial. Beyond simply checking sums or validating conversions, our quality control processes are designed to rigorously detect material errors and assess the relevance of data to client-specific reporting needs. These internal controls are essential both to build trust in the numbers we share and to ensure we faithfully represent our portfolio-level impacts.  

Bringing It All Together
What’s made this journey so fulfilling is not just the end results, but the process. The journey toward client impact reporting for 2025 includes assessing what evidence each KPI provides across the five dimensions of impact, developing decision trees for new metrics, creating tailored outputs for each client and even sitting in rooms debating whether a metric is an “output” or an “outcome.” 

Through it all, I’ve learned that aggregation is about more than data. It’s about context, collaboration, and care.

It’s about finding a way to stay true to the complexity of social and environmental change, while still making the numbers clear, comparable, and actionable. 

As someone who has always loved data, it’s been incredible to bring that passion into a role rooted in purpose. Aggregating impact may be messy at times, but it’s also meaningful. And that’s a puzzle I’m proud to help solve.