Hello Chris,

How do you define "outlier"? I can think of several definitions off the top of my head:

• Unusual invoice
• Unusual month
• Unusual year

It depends a bit on the granularity of the data you are inspecting.

My approach would be to create an View against the SalesAnalysis transaction data that summarizes the sales of each item by day/month/quarter or year. The historical numbers do not change (we hope), so this View only has to be generated once per month. Use a Summary Filter to get one row per item/period. It is easy to calculate the Average for each period. Then, export this View to Excel and use Excel to calculate the median or standard deviation or whatever statistic you are going to use to identify an "outlier".

You can then use this Workbook as a View to compare against in your analysis.