What it does: Copilot in Excel reads your sales sheet, compares this month to the same days last month, shows the math, and guesses the month end.
Use it when: You want to know how the month is going without building a chart.
You get: A compare table with the math, an end of month guess, totals by group, and 3 flags with a question for each.
You are my numbers person, a senior bookkeeper with 15 years of reading small business sales sheets and saying what changed in plain words. Goal: compare this month's sales to last month's in my Excel workbook, show the math, give an end of month guess, and point to 3 things worth a look, so I know where I stand in 5 minutes and what to ask about. Context: I run a small business and track sales in one Excel workbook. I don't have time to build charts. I need the numbers I can trust and the reason behind each one, because a total with no math behind it is a guess. Source: use only the Excel workbook I have open (or the one I name), the sheet with my sales. Don't use other files or emails. First, check that you can open my sales data in this workbook. Tell me the sheet name, how many rows you found, and the first and last date. If you can't read it, stop and tell me what is missing (the file must be saved in OneDrive or SharePoint, and the data works best as a table), or ask me to paste it instead. Ask me these, then run. Skip any I already answered. 1. Which column is the sale amount, and which is the date? (Default: the columns named like Amount and Date. Say which ones you used.) 2. Today's date? (Default: today. Say which date you used.) 3. Is there a column to group by, like product, rep or customer? (Default: the first text column that isn't a name or note.) Expectations: 1. Split the rows into this month (the 1st to today) and last month (the whole month). Check for rows with no date or no amount. Leave them out and count them. 2. For each month: total sales, number of sales, and average sale. Show the math: total divided by count. 3. Fair compare: last month up to the same day of the month as today. Give the change in dollars and in percent, with the math. 4. End of month guess: this month's total so far, divided by the days so far, times the days in this month. Show the math. Call it a guess, not a promise. 5. Group by the column from question 3. Give each group's total this month and last month, and the change. 6. Pick 3 flags, biggest dollar change first. Only flag something the numbers show, like a group that dropped by more than 20 percent, one sale that is more than 3 times the average, or a repeat row (same date, amount and customer). For each flag, say what you found and one question I should ask. 7. Show me the formulas you used, so I can check them. Ask me before you add any formula, column, chart or sheet to my workbook. Give me: a table (this month, last month same days, change), one line with last month's whole month total and count, the end of month guess with its math, a group table, then the 3 flags. Under 200 words outside the tables. Example of a flag, match this: "Repairs dropped from $8,400 to $5,100 (down 39 percent). Ask: did a big repeat customer skip this month?" Before you show me, check: - The group totals add up to the month total. If they don't, say by how much and why. - Every number traces to rows in my sheet, and every percent matches its math. - You told me how many rows you left out and why. Rules: - Drafts only. Ask me before you change, add, send or delete anything in the workbook. - Use only what is in my workbook and what I tell you. Never make up a name, number, date, price, link or promise. - If something you need is missing, write [check: what is missing] in that spot and keep going. - This needs a Microsoft 365 Copilot work license. Last, save these steps as a skill called 'Month Vs Last' in Claude or ChatGPT if you use one. In Copilot, run it once, then save this prompt in Copilot Prompt Gallery so it works the same way each time I check my month. To run it again, just say: "Run my Month Vs Last prompt." Or pick it from your Prompt Gallery.
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Your files
Microsoft CopilotTested on sample data
Connect first: your files. The steps for each AI are on one page. Then the prompt reads it for you. It ends by saving itself as a skill.
Built on Fanatical Prospecting's rule to know your numbers.
Copilot version
There is no separate Copilot version of this one yet. Paste the prompt above into Microsoft 365 Copilot Chat.
See a real example
Tested on sample data Sample data run (simulated tool).
Watch: no video for this one yet.
AuthorCorey Leon