I used to perform these calculations all the time in a previous version of
excel, but now I either can't remember how to do it, or the functionality has
changed. I have excel 2000. What I am trying to do is this:

Use data from the current worksheet and data from another worksheet in the
same workbook in a simple formula. I used to select the cell I wish the
formula to be in, then using the control key, select the various cells from
this and other worksheets that are needed to complete the SUM formula and hit
enter. Voila! the answer is there! I cannot now seem to be able to enter
data from multiple sheets into one cell as a formula. It will allow ONE
reference, but not two. Can anyone help me? I'm trying to do this by
selecting cells----I don't want to have to TYPE cell references as the
spreadsheet is too large and complex....it would take forever! Can anyone
help me?

Thank you, Tolleen