FIltering by percentile in Beast Mode/ETL
I recently had the need to filter a list of pages by pageviews. I only want pages with pageviews in the 80% percentile or higher.
This had to be done on a weekly basis. And I don't want to use a fixed-number cutoff (e.g. filter when pageview is >1,000, which is a fixed number), since pageviews > 1,000 might be considered good this week, but average the next (consider Black Friday week for example).
Appreciate any help or advice on this. I am agnostic to the calculation being done in Beast Mode or within ETL.