Everything! Analytics · Advanced
Free to readPercentile Alerts: When History Says Extreme
You don't watch the statistics panel all day. You get told when a Nations index crosses the 90th or 10th lifetime percentile on the underlyings you track — then you go look.
The core value of the Everything! statistics is knowing when a reading crosses a historically significant threshold. But you can't monitor every index on every underlying continuously. The Nations alert engine solves that: configure which underlyings and indexes matter, set your percentile thresholds, and let the engine notify you when a crossing occurs.
What triggers an alert
A percentile alert fires when a Nations index's lifetime percentile rank crosses a configured threshold — upward through the 90th (or 75th, or any level you set), or downward through the 10th (or 25th). The engine checks once per day, after the closing-level observation is computed and the statistics are updated. You configure independently for each underlying-index pair you want to watch, so a VolDex® alert on one name and a TailDex® alert on another can each have different threshold levels.
VolDex® lifetime percentile rank crossed above the 90th percentile. Today's reading is in the top 10% of all historical observations for this underlying. Condition: lifetime_pctile > 90.
TailDex® 52-week percentile rank crossed below the 10th percentile. Tail protection is historically cheap versus the past year's experience. Condition: wk52_pctile < 10.
When the lifetime percentile rank line crosses the configured threshold — here the 90th — the alert fires and notification is dispatched. The engine watches the crossing so you don't have to monitor the panel daily.
Lifetime vs 52-week alert — which to use
The alert engine supports both lifetime percentile and 52-week percentile thresholds, and they serve different purposes. A lifetime alert fires when a reading is extreme by the full historical record — structurally significant, the kind of reading that has historically been rare. A 52-week alert fires when a reading is extreme relative to the past year only — useful for detecting current-regime extremes even if the lifetime stats are broadly elevated. For most users, lifetime alerts at the 90th and 10th are the primary signal; 52-week alerts are a secondary layer for detecting within-regime extremes.
Multiple indexes, one underlying
The most powerful use of percentile alerts is cross-index confirmation. Configure alerts on VolDex®, RiskDex®, and TailDex® for the same underlying, all at the 90th lifetime percentile. When multiple alerts fire on the same name in the same session, that is a stronger signal than any one index posting an extreme alone — the options market is showing expensive vol, expensive risk premium, and elevated tail pricing simultaneously. Three alerts from three independent indexes on the same name is the kind of event worth examining closely.
An alert is a heads-up, not a trade instruction. A 90th-percentile crossing says a reading is rare by its own history. It does not say a reversal is imminent or that any particular strategy is warranted. Use the alert to go look — open the Everything! statistics panel, check the history chart, see what prior occurrences looked like. The alert starts the inquiry; the analysis is yours to conduct.
How alerts are delivered
Percentile alerts run on the Nations alert engine, dispatching by email or SMS when a threshold is crossed. Each alert includes: the underlying, the index, the threshold direction (high or low), the current percentile rank, and the computed level. The delivery is the same system that powers Nations' other index alerts — so if you already have notifications configured, percentile alerts layer into the same inbox.
Understanding alerts is free. Configuring them on your underlyings requires the tier the underlying needs: ETFs with ETF Analytics, single names with ETF + Equities. Percentile alerts on the full index suite require Everything!.
See plans →Your next step
Open the Everything! tool → Read: reading a percentile extreme → Read: this week's cross-index read →Educational content from Nations Indexes. VolDex®, RiskDex®, TailDex® are marks of Nations Indexes. Alert availability and delivery depend on plan and configuration. Nothing here is investment advice.