I am a beginning Tableau user.

For our financial reports we have our monthly outlook files that contains data like:

SBU Name

Product Name

Date

Type (PO vs ACTL/OUTL)

Volume

COGS

Revenue

Version (the version of the outlook)

All files have the same lay out. I want to be able to combine all these files into 1 data set, so I can compare what has changed outlook over outlook, do forecast accuracy calculations by comparing what the outlook was for Month 2 with the actual result for Month 2, etc.

How do I blend/join these files so I can use them as 1.