Techno thank you very much, but I have another question in relation to the same topic. The formula you discribed has to be written in every cell of the second workbook, and which is a very difficult task when there are hundreds of cells. Do you have a any short cut for this.
You only need to make that reference for one cell. Then it is just a question of copy and paste (copy cell then select the range you want to paste into and paste) and all the references will automatically be adjusted to the relevant cell in the original work-book / -sheet. If you change the reference in the formula you could even offset the referenced cells.
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'There is no such thing as a silly question, only silly answers' - Unknown
OK it sounds like you want allot of data transferred from one to another.
This procedure will do it for you
Go to the data workbook and select all the data you want copied
edit, copy
switch to the other workbook and put the cursor in the upper-left cell where you want it located
edit, past special, paste link
The second workbook will now be linked one way to the other workbook. This is only a one way deal. if you want to edit the second workbook, it will not show up in the original data.
If you want a two way data share, you will have to create one workbook and set it up for file sharing.
- Tools , share workbook
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Perfection is a subjective and abstract concept.
Two things: 1) you don't need to use the Sum formula, a simple "=" and the pointer to the other cell will do. I'm not sure, but I think it would be fastter since it doesn't have to loop through the SUM formula,
2) I'm not clear on what you're trying to do. It sounds like one sheet is the mirror of the other. In that case, why not just Copy and Paste the original after you've updated it.