Hi Gao, Many thanks for your time and reply but I found the solution today.
Our Supplier Forecast table misaligned to our internal Delivery table. I was able to match them using the query editor by:
1) Within the Delivery table, use the Group function to group the table by Date, Shop and Product ID, SUM-ing the Delivered totals.
2) I then duplictaed these columns and merged them into a Unique ID column called Delivery ID
3) I then duplicated and merged the same three columns in the Forcast table to the same Unique ID so the two tables could join.
4) Using a left outer join, I then merged the Forecast Table into the Delivery table only keeping the product decription and forecast values from the Forecast table. The newly created unique ID columns joined the data perfectly.
5) this will now allow me to write SUM and SUMX measures to create ABS values and totals.
So far, everything's talking to each other nicely. Using display cards in the reports, I can now display proper ABS Totals for the Delivery and Forecast differences, something the Matrix table wasn't computing.
The Matrix table was taking the Variance total and simply converting it to an ABS value, not SUMX-ing the product values as an ABS and SUMing those.
That exercise was a head-bender. Now I know how to join tables from two different companies to compare numbers related to each other.
Much appreciate your effort Gao. Cheers.