I am trying to do something with a workbook and hope you can help me. Not sure if I'm supposed to use an IF function or VLOOKUP or even a combination of both. Here's what I want to do:

I have 2 sheets in this workbook. Sheet 1 has dates going down a column. Sheet 1 also has a row with names on it across the top row. Sheet 2 also has dates going down a column but don't match the ones in sheet 1. Ideally, I'd like to put an "X" in the column for availability and use the dates on sheet 1 as a range (or not exact if that's easier to understand). For example, I have a part that is available on Sheet 2 for November 15th. Sheet 2 has parts that will be available on August 1, November 10, and December 2, and January 2. I want the "X" to be shown in a row across from December 2 because the November 15 date falls within that range and January 2. It wouldn't fall within November 10 because the part isn't available until November 15th. Is this possible?

Thanks,
Denise