There are (were, cannot say if fixed and in which version) a couple ones that I remember. One is not really an error, it is more like GIGO in the Average funct

There are (were, cannot say if fixed and in which version) a couple ones that I remember. One is not really an error, it is more like GIGO in the Average function: https://exceloffthegrid.com/excels-average-function-the-hidden-pitfalls/ https://exceloffthegrid.com/excels-average-function-the-hidd... The other one is actually an error due to internal number storing (floating point): https://docs.microsoft.com/en-us/office/troubleshoot/excel/floating-point-arithmetic-inaccurate-result https://docs.microsoft.com/en-us/office/troubleshoot/excel/f... More generally there is 15 digit precision that can create issues, but the "real bug" was in Excel 2007 77.1 multiplied by 850 gave apparently 100,000 instead of 65,535 https://news.ycombinator.com/item?id=59392 https://news.ycombinator.com/item?id=59392 https://www.journalofaccountancy.com/issues/2014/mar/excel-calculation-errors.html https://www.journalofaccountancy.com/issues/2014/mar/excel-c...