The user's formula looks right, but it isn't. That tiny gap between expectation and result is exactly where spreadsheets mislead even careful users. The problem isn't the math, it's the format.
When you write `=Round((Shrink/Sales)*100, 2) & "%"`, you are creating a text string. The `&` operator joins the rounded number with a percent sign, producing something like "3.45%." That looks correct, but it is no longer a number. It cannot be summed, averaged, or used in further calculations. The spreadsheet treats it as plain text. The "slightly off" feeling likely comes from a mismatch between what you see and what the cell actually contains. Rounding to two decimal places and then converting to text introduces a layer where precision is visual, not functional.
The better approach is to keep the value numeric. Use `=Shrink/Sales` and format the cell as a percentage. Spreadsheets handle percentage formatting natively. They multiply the decimal by 100 and add the symbol without altering the underlying value. That means you preserve the number for future operations while displaying exactly what you need. If you need exactly two decimal places, use `=ROUND(Shrink/Sales, 4)` and then apply percentage formatting. The rounding happens on the decimal, and the format handles the rest.
This matters because precision in percentages is not about how many digits appear. It is about whether the data remains usable. A column of text strings labeled "3.45%" cannot feed into a pivot table or a chart without manual cleanup. A column of formatted decimals can. The user's instinct to control the display is correct. The method just needs to shift from concatenation to formatting.
Our take is straightforward: stop turning numbers into text. Let the spreadsheet do the display work. If you want a percent sign, use a percent format. If you want rounding, apply it to the decimal before formatting. Your formula is close, but close in data work is the same as wrong. Fix the structure, and the precision follows.