Build an Operating Expense Waterfall

Build a month-over-month OpEx walk showing prior period, adds, reductions, and current period — visualized as an Excel waterfall chart driven by OfficeConnect data.
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A waterfall walk is how finance teams explain why a number moved. Instead of just showing OpEx went from $4.2M to $4.6M, a waterfall breaks the $400K change into its components — new hires, marketing program, software renewal, T&E reduction. This tutorial walks through building one in Workday OfficeConnect using a native Excel waterfall chart with live Adaptive Planning data.

What you’ll build: A two-column table of OpEx changes by account category, paired with an Excel waterfall chart that shows prior month, the adds and reductions in between, and the current month total.

What you’ll need:

  • OfficeConnect installed and signed in (Build Your First Report)
  • Actuals loaded for the current and prior month
  • An OpEx account hierarchy in your model (Salaries, Marketing, Software, T&E, Other)
  • Excel 2016 or later (for the built-in waterfall chart)

Step 1 — Build the bridge data table

1
Lay out the row labels On a blank sheet, in column A, type the bridge rows in order: Prior Month Total, then one row per OpEx category (Salaries, Marketing, Software, T&E, Facilities, Other), and finally Current Month Total. Leave column B for the value.
2
Add helper columns for prior and current In columns D and E (hide them later), add the prior-month and current-month OpEx values for each category. In D1 drag your Actuals version. In D2 drag Current Month -1. In E2 drag Current Month. In D3:D8, drag each category account; copy across to E3:E8.

Step 2 — Compute the bridge values

3
Set the anchor rows In B3 (Prior Month Total), write =SUM(D3:D8). In the last row (Current Month Total), write =SUM(E3:E8). These two cells are the bookends of the waterfall.
4
Compute the deltas For each category row, write =E3-D3 in column B. A positive value is an add; a negative value is a reduction. The signs tell Excel’s waterfall chart which direction the bar goes.
5
Sanity check Confirm that Prior Month Total + SUM(deltas) = Current Month Total. If it doesn’t, an account category is missing or double-counted. The full hierarchy should roll up cleanly.

Step 3 — Insert the waterfall chart

6
Select the chart range Highlight the A:B range covering Prior Month Total, all category rows, and Current Month Total. Go to Insert → Charts → Waterfall.
7
Mark the totals By default Excel treats every bar as a change. Right-click the Prior Month Total bar and choose Set as Total. Do the same for Current Month Total. The two ends now anchor to the axis baseline.
8
Polish the chart Use distinct colors for increases (positive deltas), decreases (negative), and totals. Add data labels showing the dollar value of each bar. Title the chart Operating Expense Walk — Prior Month to Current Month.

Step 4 — Refresh and reuse

9
Refresh and verify Click Refresh on the OfficeConnect ribbon. The helper columns repopulate, the bridge column recalculates, and the waterfall chart redraws automatically.
10
Hide the helper columns Hide columns D and E so only the bridge table and chart are visible. Save as a template — next month, change only the time context if you used fixed periods, or rely on relative periods to roll forward automatically.
For admins & power users For a quarter-over-quarter or year-over-year walk, swap Current Month and Current Month -1 for the relevant quarterly or annual contexts. The bridge math is identical.

Result

You now have a self-refreshing OpEx waterfall that explains the month’s movement at a glance. Executives stop asking “why did OpEx go up?” because the chart already shows them — $180K from new hires, $90K from a marketing program, offset by $40K less travel. The same template works for any month, quarter, or year.

Next steps

Last modified May 19, 2026: Rename 'Get Started' section to 'Wiki' site-wide (6ebea16d)