data table calculated on another data table's measures

Hi everyone! I'm new here, nice to meet you.

I'm getting a problem when I want to use data table to simulate different values on a cell that influence itself on another data table. I will describe my problem:

I have an experiment, where its results described on each line in table F6:J1005. I used data table for generate that table, so I get different result in each row (good).

Now, I have a side table, where I want to calculate the average of column J. But, here is the catch: I want to use data table (or any other decent way) to calculate this average for different values of offers, which are written in column G in my first table.

Clarification: I want to know the average of buyer's revenue (column J) where offer is always 10, and the revnue average where the offer is always 9, and so on.

I tried to use data table on cells M6:O15, and I put in "input cell for column" the cell G6, which I want to be changed as the value at column M. As you can see results cannot be corrected.

Any ideas how it can be simply done?