Are there any Excel experts out there that would like to have a look? I have rows and columns. If I add the columns up manually in a formula (e.g. A1+A2+A3+A4+A5, etc) the result is correct. However, if I use the SUM function (e.g. =SUM(A1:A5), the results are not correct. I have the same sort of problem when summing rows. Please HELP! Looks like an excel bug to me. I would be happy to send a small excel file to someone if they care to take a look. Thanks as always!