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GuidesBy professionFinance analysts and controllers building calculated columns

Describing a formula column in Excel, then verifying it

For Finance analysts and controllers building calculated columns.

Copilot in Excel can create new columns that calculate values from your existing data and explain how each formula works. It is fast for a first pass, and the numbers only become trustworthy once an analyst reconciles a few rows and a controller reviews it before it feeds a report.

When to use this

You need a margin, a running total or a reconciliation column across a large table, and you would rather describe what you want than hand write the formula.

  • Turns a plain description of a column into a formula plus an explanation
  • Creates new columns or rows that calculate values from your existing data
  • Explains how each formula works so you can check the logic, not just the result

Workflow

  1. Open the table in Excel and make sure your data is in a proper table

  2. Describe the column you want in plain words, such as gross margin per row or running total by month

  3. Read the formula and the explanation Copilot returns, not only the numbers

  4. Reconcile a few rows by hand against the source before you rely on the column

  5. Have a controller review the column before it feeds any report

Prompts to try

Use it, adapt it, and make it your own.

Add a column that calculates [gross margin] for each row using [revenue] and [cost]. Show me the formula you used and explain in one line how it works, so I can check it against our source figures before I rely on it.

Human lens

  • You reconcile a handful of rows by hand against the source figures
  • A controller reviews the column before it feeds a report
  • You own the tie between the calculated result and where the numbers came from

What to avoid

  • A plausible but wrong formula is a reporting risk, so tie results back to source
  • Fast output is easy to trust without checking, so reconcile before it feeds a report
  • As with any AI generated content, review, edit and verify anything Copilot creates for you

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