Hello all. Searched all day and tried many different formulas but to no avail.

Have it down to an INDEX and SUMPRODUCT function but can't quite figure it out.

Description:

Column headers are all dates, row headers are all customer names. Matrix data consists of 1,2,3,4 or 5.

I need a formula to lookup whether a 1, 2, 3, 4, or 5 appears, and result in the column header. There can be multiple values in one row so that is a complicating factor.


A1 A2 A3 A4 A5 A6 A7
Description Jul 2016 Aug 2016 Sep 2016 Oct 2016 Nov 2016 RESULT
Customer 1 1 0 0 0 2 Jul 2016, Nov 2016
Customer 2 0 3 0 2 0 Aug 2016, Oct 2016
Customer 3 0 0 1 0 0 Sep 2016
Customer 4 0 0 3 1 0 Sep 2016, Nov 2016
Customer 5 1 0 0 0 0 Jul 2016
Customer 6 0 1 0 0 0 Aug 2016

Can someone point me in the right direction? Thank you!