HVAC Inventory KPI: Revenue Lost to Stockouts Explained

Learn how to measure whether your HVAC inventory is keeping up with peak-season demand. In this lesson, you’ll build a month-by-month view of revenue lost to stockouts, compare performance against a target, and create a clear chart that highlights when inventory issues are quietly costing you jobs and margin.

Download the Excel file used in this tutorial:

First-Time Fix Rate Impacted by Parts %

1. Identify the required columns in your dataset

  • Confirm your dataset includes:
    • Date
    • Potential ticket revenue
    • Revenue lost (stockouts or shortages)
  • Keep only what you need visible so the build stays clean.

2. Extract Month and Year from the Date column

  • Create a Month field using the TEXT function:
    • Use the date cell as the input
    • Format code for month uses four M characters
  • Create a Year field using the same TEXT function:
    • Use the same date cell
    • Format code for year uses four Y characters
  • Once those helper fields exist, you can delete any duplicate test cells and keep the final Month and Year columns.

3. Create a unique, sequential list of Month and Year

  • Select your Month and Year columns and generate a unique list so your summary table has one row per month.
  • Make sure the output is sequential by date:
    • If your dataset is not sorted by date, sort it first so the month list appears in the correct order.
  • Copy the unique list and paste as values using Ctrl + Shift + V.

4. Set up the summary table headers

Create columns for:

  • Potential ticket revenue
  • Revenue loss
  • Percent
  • Target

This becomes your monthly KPI table.

5. Calculate monthly Potential Ticket Revenue using SUMIFS

  • Use SUMIFS to total potential ticket revenue for each month and year:
    • Sum range: Potential ticket revenue column
    • Criteria range 1: Month column
    • Criteria 1: The month in your summary row
    • Criteria range 2: Year column
    • Criteria 2: The year in your summary row
  • Fill the formula down for all months.

6. Calculate monthly Revenue Loss using SUMIFS

  • Repeat the exact same SUMIFS structure:
    • Only change the sum range to the Revenue lost to stockouts column
  • Fill the formula down for all months.

7. Calculate the percentage

  • In the Percent column:
    • Divide Revenue loss by Potential ticket revenue
  • Format as percent using Ctrl + Shift + 5.
  • Fill down for all months.

8. Add a target percent for comparison

  • Enter a target value (example used in the video: 2%).
  • Fill the target down the column so each month has the same benchmark.

9. Create a combined Month-Year label for charting

  • Build a chart-friendly date label by combining:
    • Month
    • Year
  • Use a simple concatenation approach so the x-axis displays clearly.

10. Build the combo chart with secondary axis

  • Select the Month-Year label plus:
    • Revenue loss
    • Percent
    • Target
  • Insert chart:
    • Insert → Recommended Charts → All Charts → Combo
  • Set chart types and axes:
    • Revenue loss as columns on the primary axis
    • Percent as a line on the secondary axis
    • Target as a line on the secondary axis
  • Confirm the secondary axis is enabled so the percent and target are visible.

11. Clean up the chart formatting

  • Make the target line thinner so it does not dominate the chart.
  • Adjust styling so the KPI line and target line are easy to distinguish.
  • Add data labels only to the line series:
    • Click the line, then add labels for that series only
    • Avoid labeling everything so the chart stays readable
  • If labels are hard to see:
    • Use the fill option on the label background to increase contrast.

12. Add totals for annual rollup

  • At the bottom of your table:
    • Sum Potential ticket revenue
    • Sum Revenue loss
  • Calculate overall percent:
    • Total revenue loss divided by total potential ticket revenue
  • This gives you the full-period KPI number for the dataset.

13. Final check before reuse

  • The hardest part is not the formulas, it is the data structure:
    • Make sure your stockout or shortage events are actually being captured consistently in your system
    • If the inputs are incomplete, the KPI will underreport the true impact

Revenue Lost to Stockouts % for HVAC Inventory

Q1. What does “Revenue Lost to Stockouts %” mean in an HVAC business?
It’s the percentage of potential revenue you lose when you can’t complete or secure work because the right parts are not available. It helps you quantify how inventory shortages impact revenue, especially during high-demand months.

Q2. Why is this KPI important during peak season?
Peak season is when demand spikes and the cost of being out of stock is highest. This KPI shows whether inventory problems are turning busy months into margin killers through delays, cancellations, or missed opportunities.

Q3. What will I learn to build in this video?
You’ll learn how to create a monthly breakdown, calculate your revenue lost percentage, set a target line, and build a chart that makes it easy to spot seasonality and inventory-driven losses over time.

Q4. How can this help improve my inventory decisions?
When you can see which months and patterns drive the biggest losses, you can prioritize stocking strategies, reorder points, and vendor planning to reduce missed jobs and protect profitability.

Q5. Can this dashboard work with ServiceTitan or other field service systems?
Yes. The key is consistently capturing the right data fields (dates, potential revenue, and stockout-related lost revenue). Once those are tracked, the same approach can be used no matter which platform you run.

Q6. Where can I get the dataset used in the tutorial?
You can download the file using the link provided near the video, or request it via email (as mentioned in the lesson).

Get more lessons like this
by joining our newsletter

Receive weekly Excel tutorials, tips, and KPIs straight to your inbox

Databoards

Analysis & Development