I'm trying to eliminate outliers from my dataset (top20% highest score let's say) by week. So I'd need to filter out (by rank) top 20% of scores from each week and then graph it on a line graph. My data is dynamic and it changes every day so I can't rank the entire data set. I need to rank by week. I've seen people talk about doing this in ETL however I don't see how that is possible.
Can you please help?