How to Master Project Prediction: From Uncertainty to Success
Watch this tutorial on Youtube.
The Challenge
You’re four months into a 12-month project. Everything looks fine. Then the update hits. And suddenly, you're tracking months late.
What just happened? And how do you explain it—confidently, clearly, and backed by real data?
In this breakdown, I’ll walk you through a simple and powerful method to forecast your project’s finish date using actual performance data. It’s fast, data-driven, and designed to help you speak with authority—whether you're talking to superintendents or senior executives.
Step-by-Step: Build a Predictive Forecast Using PAD
1. Open your schedule in P6. Start with the latest version of your schedule. Make sure all filters are off so you’re seeing the full dataset.
2. Add the right columns and remove the WBS. You’ll need:
Activity ID
Activity Name
Start
Finish
Actual Finish
Original Duration
Actual Duration
Remove the WBS before export. You want a flat list of activities—clean and easy to work with.
(Optional: Add trade, contractor, or phase codes if you want to filter the data later.)
3. Export the data into Excel. Paste your activity list into a new workbook. This is where the analysis begins.
4. Filter for completed work. Delete any activity that doesn’t have an actual finish. We’re only analyzing actuals.
5. Calculate PAD for each activity. Add a new column in Excel: PAD = Actual Duration ÷ Original Duration This tells you how much longer (or shorter) each activity took compared to plan.
6. Clean the data. Delete milestones and rows with divide-by-zero errors. Round your PAD values to two decimals.
7. Build a pivot chart. Create a pivot table with:
Rows: Actual Finish Date (grouped by month or manually formatted)
Values: Average PAD Chart it with a smooth line to visualize performance trends over time.
8. Get the average PAD. Take the average of all PAD values. If it’s 1.6, your work is taking 60% longer than planned.
9. Forecast the finish. Use this simple formula: Remaining Duration × Average PAD = Forecasted Remaining Duration Add the result to your current data date to find your new projected finish.
9.5. Want to level up? Use PAD to influence your Monte Carlo simulation. Monte Carlo models often rely on assumed ranges for durations. Now you’ve got hard data. Use your PAD as an input to define risk boundaries. You’ll bring realism to the simulation—and earn instant credibility when the model reflects actual performance.
10. Build your narrative with SCQA. Use the SCQA framework to structure your message:
Situation – “Here’s where we are.”
Complication – “But here’s the issue the data revealed.”
Question – “So what does that mean for the finish date?”
Answer – “Here’s the forecast, and here’s what we should do.”
11. Be ready to slice the data. You’ll get pushback. “Design was slow.” “Procurement messed us up.” “Construction’s going better.” Fine. Filter for just construction. Or just one contractor. Let the data tell the story.
12. Use the forecast to drive scheduling program improvements. Once you’ve shown the forecast and have everyone’s attention, this is your opportunity to lead.
Push for practical improvements like:
Track starts and finishes. Not just percent complete. Add clarity with actual dates.
Rebuild the logic. A high PAD is a signal your logic is probably flawed. Recommend a logic refresh.
Validate durations with labor and quantities. Base durations on production rates—feet of cable, tons of steel, hours per crew.
Introduce pull planning or Last Planner systems. Bring better alignment between schedule and field execution.
Create performance scorecards. Show PAD by trade, area, or contractor. Visibility drives accountability and improves results.
This isn't just about showing the problem. It’s about improving the way you plan, track, and lead.
📥 Grab the Tools
Want the actual Excel forecast template and SCQA presentation deck?
👉 You can download both right here.
Use them, remix them, and make them your own. These are the exact tools I use on $100M+ programs to forecast schedules and lead project conversations with clarity.
