Check the sheet before you send it
Open the Excel workbook Claude Code built you, follow a formula back to the data, and find out what would happen if you add rows.
Free course. Your Maestro, an AI, .
Claude Code handed you resumen.xlsx and told you the Transit count is 4,785. Before you send that sheet to anyone, check it the way you'd check one a teammate sent you: follow a number back to the data that produces it. It takes five minutes.
Open resumen.xlsx in Excel (or in Google Sheets or LibreOffice, which also open .xlsx).
Click the Transit count and read the formula
On the "resumen" sheet, select the Transit count cell (B2 in the test session). In the formula bar you'll see
=COUNTIF(datos!$D$2:$D$6452,A2): it counts, in column D of "datos" from row 2 to row 6452, how many cells match A2. To its right, in C2, the percentage divides that count by the total with=B2/$B$13.Go to where that range points
Switch to the "datos" sheet and look at column D: its header in row 1 should be
discoverymethod. Scroll to the end of the table: the last row with data should be 6452, because row 1 has the headers and the 6,451 planets sit below it (rows 2 to 6452). If the table ended earlier or later, the formula's range would leave data out.Count the same method another way
On the "datos" sheet, turn on the filter in the header row and in
discoverymethodselect only Transit. Check how many rows are left in the count on the window's status bar (or write your own=COUNTIFover that column somewhere else). It should give you 4,785, the same number B2 shows in "resumen".Check the total against the number you already know
Go back to "resumen" and select the total cell (B13 in the test session). The formula
=SUM(B2:B12)adds up the 11 methods and should give 6,451, the number of planets you found in Module 2, while the percentages add up to 100%. If the total came out to 40,350, the "datos" sheet would have one row per publication.
When all four steps add up, you've traced the number's lineage: from cell B2 in "resumen", to its formula, to the range in "datos", to the planet total you knew. You also saw why the range reaches row 6452 for 6,451 planets: row 1 holds the headers and the data starts in row 2.
The formula's fixed range
Look at the range in the formula again: $D$2:$D$6452. The dollar signs pin the start at row 2 and the end at row 6452: the function only recalculates over that block of cells.
On the previous page you saw that Claude Code typed the 11 methods into column A by hand. Together with the fixed range $D$2:$D$6452, those are choices that do the job for today's snapshot, but they matter if you plan to reuse the template later. If you're going to update that same file with future deliveries, ask Claude Code to turn "datos" into an Excel table or to reference the whole column, and check the total again.
Check a few rows by hand against the original file
The formula confirms that "resumen" correctly counts what's in "datos". What's left is checking that "datos" copied the rows correctly from planetas.csv.
Do a Glossary word with three planets spread across "datos": one from the top (row 2), one from the middle and one from the bottom (row 6452). Find them in planetas.csv and check that all three have default_flag set to 1 and the same method in discoverymethod. That's how you catch a column that shifted during the copy or a table that got cut short. If the formula in your sheet points at another column or a count came out different, tell your Maestro what showed up in your file.
Try it
Do the four steps and the three-row check on your own resumen.xlsx. Then answer: