Excel "=SUM" formula does not add up numbers correctly

I have an Excel formula issue in the formula not resulting in the correct sum, but it is not a rounding error; rather it is off by an entire cell amount. As an example, I was adding eight cells with the value of $3,001.53 which should have resulted in a total of $24,012.24, but instead I got $21,010.71 (off by one cell value). I triple-checked to make sure that the formula included all cell addresses I was trying to add, which it did. I tried deleting the formula and doing it over again, saving the spread sheet as different versions of Excel, putting the formula in a different cell location, all to no avail. There were other similar errors in the spread sheet. FYI, I am not adding concecutive cells, rather, selecting certain cells using Ctrl, left click.

 

I'm using Excel 2010 Version 14.1.6129.5000 (32-bit).

 

Please advise.

Perhaps one of the cells is Text?

Re-format all to General then F2>Enter on each.

Gord

I had this problem too. Go to Options menu under the File Tab.

Under Excel options there should be one that says Formulas and under that/beside that Calculation Options and Workbook Calculation. Make sure Automatic is checked.

@zardoz2525, check on the bottom left of the status bar to see if you have a circular reference.  Your sheet will not calculate as you would expect until you fix that, however you choose to.

Ignore that - I found that a few rows were hidden!

So it seems just incredible that a product this mature cannot even add up basic numbers.  I have a spreadsheet that the some command takes any number of positive integers...or dollar amounts and adds them all up to "0"   Just cannot imagine how flawed a product could possibly be...beyond continuing to crash regularly over a decade after it came out.   How useful is a spreadsheet that cannot add up numbers?