I have a Power Bi report where the data comes from an ODatafeed that is refreshed every 2 hours.
I can sum the amount of unpaid invoices at a point in time. For example when I look at the total on 1st April, unpaid invoices = £100
Invoices will be paid, and new ones will be generated. When I look at the total on 1st May, unpaid invoices = £75.
How do I calculate “total amount the unpaid invoices has CHANGED since last month” in other words £100 - £75 = £25?
I cant work out how to capture the £100, since that data has now changed.
I need to capture the data at a point in time (without manually exporting the data to Excel every month).
How do I do it?