I have multiple price tables that go along a worksheet that are for different
products. For each product there is a:
Low High Average
These prices are reported weekly and the week is on the first column.

I am trying to use a lookup prices so that I can average them by year,
quarter and month. I created a unique ID for each product that is found in at
the top left hand corner of each table so that I could use the offset
function to find the starting reference point but now I am stuck as to how I
can get it to perform the average once I have identified which table it is
meant to grab the information from.

Any help would be much appreciated.