Identify new item

[Memar]

I have a master data workbook which I use to return/update data to different workbooks using a SumProduct function with three criteria every month. Occasionally, a new product type is included in the master workbook, but accountants forget to record the new product to one of the workbooks where it needs to be recorded. As a result, any information related to the item will not be updated/returned to other workbooks monthly. Is there a way to identify a new product (using Excel) which doesn't not match to the other workbooks in the first month it was loaded to the master workbook? example color code, different font etc...

Thanks for your help and time.