Hey, I have a question regarding percentile capping. We have a metric for Net Deposit (total deposits minus total withdrawals). Because this value can be both positive and negative, we have outliers on both ends of the distribution. Is it possible to apply two-sided percentile capping - capping at both the 95th percentile (upper tail) and the 5th percentile (lower tail) simultaneously? Or does Growthbook's percentile capping only support one-sided (upper) capping?

I think its only one sided - but I can check with @helpful-application-7107

Thanks @fresh-football-47124! If it is indeed only one-sided, would it be possible to log this as a feature request for a future update? Two-sided percentile capping (lower + upper tail) would be really useful for metrics that can have both positive and negative values, like our Net Deposit metric. Happy to provide more context if helpful! cc. @helpful-application-7107

Yeah I understand the use case. A table of transactions and you want to cap after aggregating, not before at the transaction level.

Hey @helpful-application-7107! The capping is happening after aggregation, that part is correct. The issue is that currently only the upper tail (95th percentile) is being capped, with no way to cap the lower tail (5th percentile). The table below illustrates this perfectly — using dummy data as an example: • User 1 has a Net Deposit of -£9,500 — a huge negative outlier with no way to cap it • User 10 has a Net Deposit of £1,000 — capped at the 95th percentile (£300) ✅ You can see in the Mean Net Deposit summary at the bottom: • No capping → -£891 — badly skewed • Current (95th percentile only) → -£1,011 — the negative outliers are still dragging the mean down • Requested (two-sided capping) → -£39 — far more representative So the feature request is simply the ability to apply a lower-tail cap in addition to the existing upper-tail cap. Would this be possible to log as a feature request? 🙏

Hi @fierce-london-55569 please feel free to log this feature request as a GitHub issue in our repo here- https://github.com/growthbook/growthbook/issues This will auto subscribe you to the issue so that you're directly notified by the Engineering team on any updates 🙌

Hey @fierce-london-55569, it looks like we have an open ticket for this and there's a PR in the works linked there.

thanks both for your support! Much appreciated.

Our pleasure to assist 🌻