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If the data is identical, why not just copy it? (why do you need 2 identical files?) How is infor getting into the Yearly file? The yearly file is the tab labeled 2017 correct?
in the master tab you could have an IF formula to update the 'Master' tab from the '2017' tab. It's not clear what you want to accomplish. Give my attachment a try
what does your 'complied' data look like? If files are set up with identical columns, you can copy monthly and layer data ( at end of August add August...) Otherwise punt! Some sample data would sure have been nice.