2 monitors on one PC, I assume?

You can set up the PC to show one Excel window spanning the two
monitors (don't ask me how, but I've seen it done)

Then have the two sheets of your workbook in separate windows within
the one Excel window (Window New Window), and arrange them side by
side (Window Arrange Vertical). One should now appear on each
monitor and, being in the same instance of Excel they will certainly
update as you enter data in automatic calculation mode).

If your monitors are on different PCs then Excel is not the program you
should be using - Access would be better as it is designed for multiple
simultaneous use of the same data by different people.

Bill Manville
MVP - Microsoft Excel, Oxford, England
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