Hi Bill,
Yes, we developed our own queries. We did them as views for external queries, before the ability to do subqueries came out, so they are on our SQL server. If they were BAQs I’d share. I’m sorry 
We developed them because we could not find any out of the box means in E9.
I think you want to pull all part trans records for consuming transactions and sum for a day, or a week, or a month, and then get avg and stddev across those days, weeks, or months. We use weekly average usage. There are some other posts where people developed reports or dashboards with average usage, such as here:
Inventory Usage dashboard - summaries Monthly horizontally?
and here
Inventory Usage BAQ Report
Inventory Usage BAQ?
I wonder if they are still in group and might have helpful suggestions.
Nancy