When viewing the current month filing data, I need to identify all prior period loads

[Deniqua11]

Hello guys! 

I'm in the process of creating an Alteryx workflow to identify prior period transactions within my current filing period data. (Ex: I'm viewing Jan 2025 data, but need to identify loads prior to that date.)  I used the union tool to combine 3 spreadsheets with the same data (just different entities) to compare to our Avalara export of transactions that were filed last filing period. I then used the joining tool to join all 4 spreadsheets together. Now I'm stuck trying to figure out a formula to identify the prior period loads within the data. Any guesses?? 

[OTrieger]

@Deniqua11 

Add in the Data Input tool the File name, that might help you recognize from where the data came.

[binuacs]

@Deniqua11 can you upload some sample files and expected output to understand your use case better?