Getting the average of values who share a value in a different column in Excel

Question

I am messing around with Excel 2007 and I'm looking for a solution regarding finding the average of values who share a value in a different column.

The values in column A are all numbers running anywhere from 0 to several dozen. Column B has either Yes or No in it, one for each row. What I am looking for is being able to calculate the average of all values in column A who share the same word in column B.

Initially both will be empty, and only after the field in column A has been filled will column B be filled. The value of column A does not always mean that it always have the same value in column B, meaning that that two instances of the number 8 in A can mean that either, both or neither values in B will be Yes.

I am looking for two formulas to give me these averages: one average for all the Yes numbers and one for all the No ones, but not in VBA.

Thank you in advance!

Answer 1

Not sure I understand, but please try say in D1 and copied down one row:

=AVERAGEIF(B:B,C1,A:A)  

where C1 is Yes and C2 is No.