Has anyone here successfully used the AGO() time series function in Eloqua Insights?

Summary:

I am trying to build a report showing total email sends for the previous month in the same row but the time_level parameter doesn't seem to be working the way I expected.

If I put Day, Month, Quarter or Year, it gives me this error:

nQSError: 27037 Unresolved level: 0:0

And if I use the email send day, week, month or year columns as the time_level, my reports shows a blank result for my AGO() formula.

Does anyone have a working example of this that they can share?

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