Compare two data tables and find a match, then return a column header from the first table

Hello,

I am trying to figure out how to compare two data sets, find a match, and then return the column header from the first data set.

To further clarify, the first data set is a recurring production plan for a given product line. It depicts dates that certain activities need to start in order to meet final delivery goals for each unit produced. Here is an example:


Unit #1 Unit #2 Unit #3
Task 1 1/5/2016 2/5/2016 3/5/2016
Task 2 1/15/2016 2/15/2016 3/15/2016
Task 3 1/25/2016 2/25/2016 3/25/2016

I have about 30 different product lines in separate worksheets with this type of data and structure. The tasks are unique to each product line (eg there is no corresponding task 1 in any other product line).

What I am trying to create is a summary table that will give me a one-year aggregate view of all tasks and when they need to start. The column headers in the summary chart are calendar days, and the row headers are all the different tasks from each of the product lines. I want to compare dates in the product line worksheets to the calendar dates in the summary worksheet, and when there is a match, I want the Unit Number to appear in the summary chart:

01-Jan-2016 02-Jan-2016 03-Jan-2016 04-Jan-2016 05-Jan-2016 .... 15-Jan-2016 ....31-Dec-2016
Task 1 Unit #1

Task 2 Unit #1

Task 3

And so on. Any help would be greatly appreciated.

Andy

Sorry, folks. New to the forum.

I have attached a file that shows what I am attempting to do. First tab is a dummy production plan for a given product, detailing start dates by task and by unit. In my real file, I have about 25-30 separate product plans, each on a separate worksheet. The start dates are not evenly distributed as they appear to be in my dummy file. The attached file is the newer version of Excel, but my real file is located on my work computer which runs Excel 2007.

My goal is to create the summary tab, which is depicted in the second tab of the attached file. I need to match start dates in the product worksheets with the calendar dates in the summary tab. When there is a match, I need to populate the summary cell with the column header from the product worksheets (eg Unit #1, Unit #2).

It seems like it is an INDEX MATCH combination but I am totally missing it.

Any help is appreciated.

Andy