Ok great. Thank you so much for all of your help xld! I have another, what I hope is a 'quick' question.

I would like to modify the condition:

=SUMPRODUCT((ISNUMBER(Y!$1:$3))*(Y!$1:$3<=Z!A1)*(X!$B$1:$B$3="T"))
such that instead of = "T"

it could be

="C" OR ="K"

with the 1st two conditions still the same.

The 1st two conditions are still the same though.



And while I am here, I would need another one such that instead of

= "T"

it must be

="C" AND ="K"