title: Index Match Match across multiple columns
body: <p>I have an Index Match Match question that I have not been able to find the answer for in researching. Although the solution may actually might be different than an Index Match Match formula - I'm open to try something more efficient than my current workaround.</p>
  
  <p>I have one worksheet with data from my company on it. We sell a Product (let's call it Coke Zero) and we track the weeks that we put a promotion on and how much profit we make by selling it to the retailer. For example a promotion for Coke Zero starts the first week of Jan and ends 3 weeks later and we make a gross profit of $100 each week the promotion runs. I then have an external database with sales data formatted on a weekly basis to tell me how many units of Coke Zero I sold in each week. My internal data has thousands of lines like this with dozens of products, however the promotions are consolidated on one single row regardless of if it runs for more than one week, making matching up to the external database difficult. I need to create a lookup for what our Gross Profit was for each week of the promotion.</p>
  
  <p>I have attached an example image of the workbook + two data sheets of what I've tried to do, summarised below.
  On the Internal Data Sheet I've created additional columns to the right with all of the weeks listed that the promotion is on for, and concatenated them with the Product Code to be able to match week by week to the data in the External data sheet. Then my lookup basically checks every column one after another until it finds one where the concatenate of Week_Product Code concatenate matches.</p>
  
  <p><img src="https://i.stack.imgur.com/UctK9.png" alt="Example Screengrab from Excel Workbooks"></p>
  
  <p>My current solution technically works but my final formula is really slow and cumbersome given the data can be anywhere from 10K-200K lines when looking at multiple retailers. I was hoping to find a more efficient formula to complete the lookup.</p>
  
  <p>Current solution on the External Data Sheet Column E:</p>
  
  <pre><code>=IF(ISNUMBER(MATCH(D2,'Internal Data'!$E:$E,0)),INDEX('Internal Data'!$D:$D,MATCH(D2,'Internal Data'!$E:$E,0)),
  IF(ISNUMBER(MATCH(D2,'Internal Data'!$F:$F,0)),INDEX('Internal Data'!$D:$D,MATCH(D2,'Internal Data'!$F:$F,0)),
  IF(ISNUMBER(MATCH(D2,'Internal Data'!$G:$G,0)),INDEX('Internal Data'!$D:$D,MATCH(D2,'Internal Data'!$G:$G,0)),
  "0")))
  </code></pre>