I've got a list of 4 columns which log the date of submission to different suppliers. In the 5th column, I've got 1 list that says when either of the suppliers responded.

Is there any way I can count the number of responses in the response column, dependant on which supplier?

i.e. If I submit 5 items to 1 supplier, and 4 items to another supplier, how can I write a formula that says, if the cells in this column aren't blank, then count the number of entries in the response column?