Outstanding Amount

 I'm trying to write a function that  returns just the outstanding_amount the same as in the 7 Buckets report. I intention is to use this returned value in one of my Materialized views as a column on our weekly backlog report. I was thinking of calling the ARPT_SQL_FUNC_UTIL.get_balance_due_as_of_date and bucket_function but there seem to be a problem with supplying all of the required parameters.
If anyone knows of any other easier way to accomplish I would appreciate if you can share the knowledge. We are running Oracle EBS 11.5.10.2.

Thanks,

Leo