If by "down to 2 places", you mean that you are formatting to display 2 decimal places, that is not sufficient.

Formatting alone only affects how a value appears. It does not affect the actual cell value.

Moreover, as my example with 10.01 - 10 demonstrates, constants might have only 2 decimal places, but calculations with those constants might result in values with more decimal places because of the binary arithmetic anomalies that I alluded to before.

Finally, if results are significantly off (by 50+ cents, for example), the mistake could be in your calculations. Not really a mistake per se; but again, failing to round calculations based on your expectations.

For example, =12.45*10% in A1 is 1.245. That might display 1.25 if you format to 2 decimal places. So you might expect a subsequent calculation like =A1*10 to be 12.50, but in fact it is 12.45. And if you sum a bunch of calculations like my example in A1, the cumulative effect can be a significant "error" -- that is, a deviation from your expectations based on displayed values (appearances).

For all of these examples, the remedy is the same: explicitly round to the precision that you expect calculations to be accurate to. That means: use the ROUND function.

Did you even try it?


As I said, upload an example Excel file (redacted) that demonstrates the problem to a file-sharing website, and post the public/share URL here.

One such website is box.net/files. After uploading the file, be sure to click on Share to get the public URL.