Formula for checking repeat data

I have a task with my new job that I pull an excel report every Monday. What I have to do is check what has dropped the new list that was on the old one and find the items that have been added that were not on the old list so I am checking Last Mondays list with this Mondays list. What I would like to do is add the sheet from last week to the workbook and use a formula that will tell me comparing cell B from Sheet 2 to cell B in sheet one. The following below is an example.

Cell B (Sheet One) Cell C (Sheet One)
1234 NEW
4321 DROPPED
5678 REMAINS
5555 DROPPED
5456 NEW

This will help me report to leadership our progress from eliminating these items.

Any help would be greatly appreciated.