Excel and Spreadsheet Tips
How To Use Python in Excel for FP&A: Use Cases and Examples
Learn how to use Python in Excel for FP&A use cases such as forecasting, predictive modeling, and data cleaning.
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If the past few years have taught finance teams anything, it’s this: forecasts can’t be static.
Think back to 2020 when the COVID-19 pandemic upended business and life as we knew it. Models that once felt solid suddenly became obsolete as projects froze and policies changed. Nearly a quarter of FP&A teams had to reforecast daily or weekly, and over half updated monthly, according to the Association for Financial Professionals (AFP).
Since then and even now, disruptions haven’t slowed—like the Trump tariffs in April 2025, affecting global supply chains and forcing companies to adjust their models again.
While some teams have had to scramble to keep up, others have successfully built agile scenario planning models in Excel that can adapt to sudden shifts like these.
At Excelerate Finance 2025, two FP&A leaders shared their insights on how they’ve built models within Excel that helped them turn chaos into clarity in 2020 and even today.
We break down their approach in this article, with actionable takeaways to make your own forecasts just as resilient.
Vena Co-Founder and Chief Solutions Architect Rishi Grover showcases how you can use modern Excel features, such as its integration with Python, paired with Vena to do advanced scenario modeling.
Brandon Combs leads the finance team at Young Life, a global Christian youth non-profit operating in 102 countries with large-scale camp facilities across 17 U.S. states. Kristina Bittorf, on the other hand, was the Senior Manager of FP&A at Sprout Social during the pandemic and now heads the finance team at Aeropay (both of which are software companies).
Their worlds couldn’t be more different—a faith-based nonprofit and a fast-growing public tech company—but both have had to adapt their scenario planning models to withstand sudden market shifts and keep cash flow steady in uncertain times.
Here are five ways they’ve done it with Excel and modern FP&A software, and how you can put the same strategies into practice.
Creating a repeatable process for how you’ll update your financial outlook as new business conditions emerge helps you take action faster when it counts.
It means connecting real-time operational and financial inputs—like costs, sales, or churn—to your core key performance indicators (KPIs), so your forecast evolves with the business rather than trailing behind it.
For example, if there’s an unexpected revenue shortfall, a surge in customer demand, or a rise in supplier costs, you can immediately feed that data into your forecast. This lets your team and leadership see how it affects the business’s priorities in real time and make adjustments to capitalize on opportunities or mitigate risks before they become issues.
As Rishi Grover, Vena Co-founder and Chief Solutions Architect, put it:
“Gone are the days of the fixed annual budget. We now need to re-forecast on a much more frequent basis and be able to bring in your latest set of financial and operational actuals to help supercharge these models and also help support scenario modeling.”
That’s why it’s critical to create this framework before disruption forces your hand.
First, connect your core systems and departments.
Finance, sales, HR, and operations should feed into a single forecasting model so actuals update automatically, and they can immediately see the ripple effects of their decisions. This foundation makes it much easier to layer on scenario planning or rolling forecasts.
With Excel alone, you can connect inputs from finance, sales, HR, and operations into one model, but the process is manual. Actuals need to be copied or imported regularly, which creates delays and leaves room for errors. With Vena, however, you can directly connect your source systems into one database while keeping the Excel interface that your finance and extended teams already know, making live reforecasting easier.
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A view of how Vena can update data from your source systems in real time within your Excel reports.
Brandon saw this benefit firsthand.
Just a month before COVID-19 hit, his team had rolled out a new forecasting process, centrally managed in Vena. So when camps across 30 properties had to shut down, they moved straight into reforecasting mode instead of scrambling to build new processes.
The team updated forecasts constantly—sometimes every week—to reflect restrictions and significant revenue losses, including $100,000 in canceled weekend group rentals. Because their Excel templates were centrally managed in Vena, they could set new expense reduction targets, revise revenue projections, and share updates across the organization in minutes.
Using Excel’s conditional formatting function also made it easy for budget owners to see where they stood—red if they were short of targets, green when they met them—so they could act right away.
The live forecasts gave leadership a clear view of the organization’s financial reality. So, when a workforce reduction became unavoidable in August 2020, those insights helped limit the number of people they had to lay off.
"Without the live forecasts, the work done by our 230 licensed end users, and the budget ownership at the local level, the cuts would have been far deeper. We were able to keep far more people on staff than we otherwise could have, and Vena helped with that."
Brandon Combs, Senior Director of Camp Finance, Young Life
Prioritizing the right drivers ensures your forecasts reflect what truly impacts revenue, costs and growth. Without them, you risk building scenario models that look great on paper but don’t translate into actionable business decisions.
A 2025 FP&A Trends survey confirms this. 77% of organizations using driver-based models rate their forecasts as good or great, compared to just 38% among those that don’t use driver-based models.
That difference highlights an important reality: every company has its own unique set of internal and external drivers. Tying them into the budgeting and forecasting process lets you allocate resources to the areas that influence performance most and clearly see the impact of those choices over time.
Start by identifying the small set of variables that explain most of the variance in your revenue and costs. These will look different depending on your business model.
The goal isn’t to track everything, as too many drivers dilute the model and make it harder for leadership to act.
“What really matters is identifying the more material and significant drivers. There are endless variables you could integrate, but you don’t need to include them all. As FP&A professionals, we can plan all day, yet there will always be things that catch us off guard. Sometimes you miss a rate or don’t load something correctly, but by the end of the month, you realize you’re still within 5%. That’s the art and the craft of this work—prioritizing what’s actually important and financially significant.”
Kristina Bittorf, Head of Finance, Aeropay
Every company will have its own set of core drivers depending on its industry, how it generates revenue, and the sources of its biggest costs. These drivers should reflect how the business generates value, which means looking beyond just financial inputs to the operational levers that directly influence performance and outcomes.
At Sprout Social, Kristina recalls that the primary drivers were sales headcount and the revenue directly tied to the productivity of that team. But at Aeropay, a payment processor for the gaming and betting industry, the story looks very different. Because the business is highly transactional, the finance team focuses on variables at the unit economics level.
For them, their biggest drivers are ACH bank origination fees, as well as their ability to predict and collect payments from players placing bets.
Because a customer might place a bet even if they don’t currently have enough money in their account, Aeropay came up with a way to manage that risk. The payment processor connects to a database from the top 20 U.S. banks, giving them a clear view of customers’ average account balances and typical pay dates. Using these insights, they can accurately forecast when funds will be available to collect.
For Young Life, a nonprofit that runs summer camps, its biggest growth driver isn’t financial at all. It’s the number of volunteer leaders in a given area. More leaders mean more kids can attend camp. Camp fees also play a role, but the nonprofit’s ultimate goal is to keep fees low enough that more kids can come, while still covering the costs of food, beds and facilities.
To choose your own drivers before running scenario analysis in Excel:
Look at past performance and ask: which variables consistently moved the needle on revenue or costs? Those are your first ones to start tracking.
Break your revenue target into concrete levers that drive it, such as sales volume and pricing, and use those variables as drivers.
Map out the resources required to support your sales targets. Hiring needs, training hours, tech investments, or customer support ratios are examples of operational drivers that directly influence whether sales goals are achievable.
Tie every department’s budget and assumptions back to the same set of core drivers. For example, Marketing (cost per lead), Product (feature adoption), and Finance (payment collection rate) should all roll up to the sales and operational levers.
Secure executive buy-in, as they need to understand and back the critical drivers you’ve identified so that you can set organization-wide goals around them and collaborate with other departments.
Even the best forecasting models fall short if they rely only on siloed data. Internal data tells you what has historically moved the needle in your business, while external data captures shifts happening in the wider market.
For example, forecasting based on sales headcount might look solid when based only on past productivity. But what happens if hiring slows because the labor market tightens, or if average deal size shrinks due to increased competition? External context matters.
When you bring both internal and external data into a single forecasting environment, you can stress test assumptions, track patterns in real time, and give leadership a clearer view of what’s really driving performance.
This turns your forecast from a static snapshot into a flexible, forward-looking tool. So when conditions change, you're not caught off guard. Instead, your scenario model shows how those shifts impact revenue, costs and margins.
This is where a modern FP&A platform adds real value. It gives you a single environment to connect internal and external systems, automate data updates, and keep your models live.
Both Brandon and Kristina rely on this type of data integration to build and update their forecasts. At Young Life, Brandon's team pulls from Salesforce for donor tracking, SQL Server databases for operational data, and Workday for actuals.
“All our Workday actuals go into Snowflake, and from there, we extract into Vena,” says Brandon.
At Sprout Social, Kristina and her team worked with multiple systems too—Workday for HR data, Salesforce for revenue reporting, and NetSuite for ERP. Like many SaaS companies, their challenge was making sure it came together in one place, in the right format, and at the right time to power reliable forecasting and KPI tracking.
“For the longest time, even with a Salesforce team of five-plus people, I couldn’t get the system to automatically pull the snapshot I needed at 10 pm Eastern every single day," she explains.
“One of the first things we did in Vena was to get it set up. We were able to do better reporting in Vena than we ever could in Salesforce alone. From there, it fed directly into our financial models and merged with our NetSuite integration, so we could track all of our key SaaS KPIs. It also tied into workforce planning through Workday. With Vena, it was all just way easier.”
When running your “what if” analyses based on your connected data sources, what this looks like will vary by industry.
For Kristina, scenario planning as a payment processing company means testing sensitivity around gross margin levers like banking fees and transaction costs. For Brandon, it’s about adjusting attendance forecasts and modeling inflation on core supplies such as food and paper goods.
“We use a sophisticated tool that pulls in a boatload of data and helps us determine whether to plan for a 2%, 3%, or 4% adjustment. We also weave in external indicators like the consumer price index and producer price index to account for inflation on commodities. And because we buy a lot of essentials, like bacon and toilet paper, that’s a huge factor in our modeling.”
Brandon Combs, Senior Director of Camp Finance, Young Life
For most finance teams, Excel is still the go-to tool for building scenario planning models. In Vena’s 2025 State of Strategic Finance report, 89% of finance professionals we surveyed said they still use Excel despite having other planning software in place, with financial modeling and calculations being the top use case they rely on it for.
That means even if your company hasn’t adopted an FP&A platform yet, or you simply want to stick with Excel, you can still do a lot more beyond static spreadsheets and manual formulas. Today’s Excel is equipped with modern features that make it possible to automate data refreshes, connect to external sources, and run powerful scenario tests that used to require far more technical tools.
One of the biggest upgrades is Python in Excel. If you have a Microsoft 365 license, you’ll see the “Insert Python” option, which essentially brings a full Python development environment directly into Excel. This gives finance teams the ability to build correlations, test sensitivities, and even apply machine learning models on top of their forecasts.
For teams without deep coding skills or access to a data science team, tools like Microsoft Copilot can generate or explain Python code.
Other Excel features that make forecasting and scenario planning more dynamic include:
XLOOKUP and LAMBDA: Cleaner, reusable formulas that replace clunky workarounds.
Analyze Data: Run quick, AI-powered insights and detect trends.
Excel Solver: Optimize different input mixes to test outcomes.
Slicers, checkboxes, and Office Scripts: Build interactive dashboards and automate steps so that stakeholders can explore assumptions without breaking the model.
The most advanced forecast won’t move the business forward if stakeholders can’t understand or engage with it. That’s why you need to make your models transparent, collaborative, and accessible to the people who use them to make decisions.
When that happens, they stop being “finance-only” tools and start becoming invaluable assets for cross-functional planning and decision-making across the entire organization.
“The number one thing that makes us all really successful at our jobs is our ability to bring people into the work that we do. When people can see the importance and the impact of our work, it makes it easier for us to put things together. The transparency, the ease of reporting, and the fact that we can customize how reports look in Vena really set us up well. People feel more comfortable and feel like they have transparency to their data.”
Kristina Bittorf, Head of Finance, Aeropay
As both Kristina and Brandon pointed out during the talk, transparency builds trust. And when stakeholders are confident in the numbers, they can focus on making decisions.
Finance leaders who succeed are the ones who treat their forecasts as a living thing. Instead of locking themselves into a fixed plan, they build models that adapt to market shifts, highlight the most important drivers, and equip leadership and cross-functional teams with real-time insights to make confident decisions. That’s what helped Brandon and Kristina.
The good news is that you do not need to reinvent the wheel to do this. Excel can take you far, and a platform like Vena builds on that familiar foundation. It consolidates your data, models, and workflows into a single environment, allowing you to build dynamic forecasts. You can update assumptions quickly, test “what if” scenarios in minutes, and prepare your organization to respond to change instead of being caught off guard.
The earlier you build agility into your forecasting models, the better prepared you will be for whatever comes next.
Ready to make your scenario planning models more agile? Book a demo and see how Vena can streamline your FP&A process, connect your data in one place, and help Finance become a trusted partner to the business.
Watch Brandon and Kristina’s full session from Excelerate Finance 2025.
Watch NowJessica Tee Orika-Owunna is a content strategist and writer with over seven years of experience creating and repurposing relatable, helpful content for global brands including Contentsquare, Softr, Hotjar and Vena. She specializes in turning everyday product, user, and subject matter expert insights into product-led content that answers real buyer questions and supports better business outcomes.
