This is sometimes referred to as a "cross tab" report.
It's not the simplest type of report to pull together in FileMaker, but it can be done.
What version of FileMaker are you using?
How are your tables and relationships defined?
Do you have a table where each record records a single sales transaction for a given customer? With links to a customers table, perhaps?
Each row in your example, including the year and month column headers could be sub summary layout parts.
The cells showing a total for each month for a given customer could be portals, probably flitered portals.
In FileMaker 12, the cells could each be 1 of 12 calculation fields that use ExecuteSQL() to compute the totals.
A Lightweight Cross-Tabular Data Entry Method
Example File Download Example File
Cross Tab Summary Report
Download - Cross Tab Summary Report (0.8 MB)
My ScoopIt site about Filemaker - http://www.scoop.it/t/filemaker-info/
Thanks for your reply, you helped me before in a previous database I was making. I am very grateful for your help again.
I am using Filemaker Pro 12.
I have just started this current database and at the moment have only built one table. Im sure I will need more tables such as a customer table, but I didn't want to get involved to much without first knowing if the result I wanted to create was possible.
I will attach some pictures of what I have so far.
When I was playing around with the database, I could produce a long list of sales by customer by month and by year, but this would print out over maybe 6 pages is not as elegant as a one page matrix that I would like to atchieve. A one page matrix is much easier to understand at a glance.
I will look into your suggestions.
Thanks also David for your reply, I will take a look at your website.
What I outlined in my previous post can be used with your current single table to produce the cross tab report that you want via a self join or a set of calculation fields with ExecuteSQL.
What I outlined and what is spelled out in David's links should be variations of the same idea so let me know if they provide what you need or not.