Calculate running totals and averages

Calculate running totals and averages in Microsoft Excel — with the four heights of help laid out: do it now, make it easier for the next person to accept, work out the right move when you are stuck, and learn the pattern so it stops coming back.

4prompt heights
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The four heights

The same task, four distances: today's deadline, the next reviewer, the stuck moment, the pattern.

Execute — do the immediate task

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I need the monthly sales sheet turned into running totals and period averages so finance can verify…
I need the monthly sales sheet turned into running totals and period averages so finance can verify forecasts. Add a running total column that restarts at the fiscal year boundary and an adjacent 3-month rolling average. Put the running total directly to the right of Sales, the rolling average next. Check row 120 for anomalies before I hand it to Martina by Friday.

Improve — make it easier to accept

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Before I hand this to the FP&A lead, make the running totals and averages instantly visible and…
Before I hand this to the FP&A lead, make the running totals and averages instantly visible and defensible. Move the fiscal-year running total next to Sales, label it ‘FY Running Total’ and surface the 3-month rolling average up top. Flag rows where the running total drops or the rolling average swings more than 25% month-on-month and add a brief footnote explaining how year boundaries are handled.

Decide — diagnose the stuck moment

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I added a running-total column and now totals look inflated across the fiscal year change; Martina…

I added the running-total column and some totals double-count at the year boundary

I added a running-total column and now totals look inflated across the fiscal year change; Martina will review tomorrow and I can’t explain the spike. I’m not sure if my formula reset is wrong or the fiscal-boundary flag. What’s the most likely cause and the quickest fix so I can show a corrected sheet before the meeting?

Become — change the pattern

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Every quarter I rebuild running totals and rolling averages by hand and end up firefighting…

I keep rebuilding running totals every quarter from scratch

Every quarter I rebuild running totals and rolling averages by hand and end up firefighting boundary errors and formula drift. It costs hours and undermines trust with Finance. What habit or automation should I adopt so running totals are correct, auditable, and I stop redoing this work each quarter?

Next to this one

Other spreadsheet work people do in Microsoft Excel.

Every task here came from the work, not from a feature list — which is why the prompts name what you want done and never the button that does it. The tool changes; the work does not.
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