@erik_tarnvik, I have just applied the new solution, but it looks like this time again the subtotal reverts back to the total (includes sum from the blanks). Example below.
Thanks again for all this help, I am new with DAX language and all this back and forth helps me to learn something new eery time!
Really appreciate it!
Hi @katalay, you are right, I failed to see that side effect. Turned out I struggled a little to solve this and had to take a different approach. I am still not satisfied that this is the simplest possible solution but it does work using my example data:
ALL_2016_NEW = CALCULATE ( SUM ( YOY[MKT_2016] ), SELECTCOLUMNS(FILTER ( SUMMARIZE(YOY,YOY[Month],YOY[MKT_2017]), YOY[MKT_2017] <> 0),"Month", YOY[Month]) )