Every tier shows live index readings and the analytics tools. Everything! adds the complete daily archive back to 2005, lifetime and 52-week summary statistics (percentile rank, z-score, high, low), and CSV download — on every Nations index on every tracked underlying. The history is the differentiator: a reading is only meaningful compared to its own past.

The percentile rank for today's reading is: of all daily closing-level observations in the archive for this underlying and index, what fraction are strictly below today's value, expressed as a percentage. A rank of 87 means today's reading is higher than 87% of all historical readings. It is computed empirically from the sorted archive — no distributional assumption.

The z-score is (today's reading − mean) ÷ standard deviation of the reference period. A z-score of +2 means two standard deviations above average. It differs from the percentile rank because it is sensitive to the shape of the distribution — if the distribution is right-skewed (as vol indexes often are), a +2 z-score may correspond to a different percentile than in a normal distribution. Use both: the percentile is distribution-free; the z-score captures distance from the center.

Lifetime statistics place today's reading against the full archive — structurally significant across all market regimes since 2005. Use them to ask: is this rare by market history? 52-week statistics compare only to the trailing year. Use them when the current regime may differ from the long-run average — for example, if the market has been in a persistently elevated-vol environment, the lifetime rank will be high for everything; the 52-week rank shows what is elevated within the current regime.

For major ETFs (SPY, QQQ, IWM, TLT, GLD, and others), the archive traces back to 2005 — the earliest date at which Nations considers the underlying options data clean and liquid enough for reliable index computation. For individual single names, coverage begins at the earliest date where reliable data exists, which varies by underlying. The coverage start date for each underlying is displayed in the archive panel.

Every Nations index for which daily histories are computed: VolDex® (at-the-money implied vol), CallDex® (call-side implied vol), PutDex® (put-side implied vol), RiskDex® (implied risk premium), TailDex® (tail-risk premium), TermDex® (implied term structure), and the analytics tool readings. All are available on all tracked underlyings, with the full archive and statistics.

The CSV has one row per trading day: date (ISO format), closing index level, lifetime percentile rank, lifetime z-score, 52-week percentile rank, and 52-week high and low. Statistics columns are populated after sufficient history accumulates. To update, re-download the full file — it is always a complete, clean replacement. For a daily pipeline, download and append only rows after your last local date.

Yes — that is one of the primary use cases. The CSV archive is the signal series; pair it with the Nations Strategy Backtester, which accepts index histories as inputs and tests strategy rules against them. Be careful about look-ahead bias: the platform's pre-computed statistics use the full archive, so for a rigorous study, compute rolling percentile ranks using only data available at each point in time.

A cross-index read compares the percentile ranks of multiple Nations indexes on the same underlying simultaneously. When VolDex®, RiskDex®, and TailDex® are all at the 90th+ percentile on the same name, the signal is much stronger than any one index alone — multiple independent dimensions of the implied distribution are confirming the same picture. When they diverge, the divergence itself is informative.

Yes, occasionally. Options market data can carry minor revisions as data sources are corrected or supplemented. Nations updates the archive when improvements are identified. The general guidance is: re-download periodically rather than treating an old download as permanently authoritative. Major structural revisions are rare; day-to-day precision revisions are occasional. The methodology documentation describes the data sources and revision policy.

No. High percentile rank means the reading is historically rare — near the top of its distribution. It is context for a decision, not a forecast. Readings at the 90th percentile can persist for weeks or months during genuine stress periods. A high rank tells you where you are in the distribution; it does not set a timer on when mean reversion occurs.

In the Everything! platform, navigate to the Alert configuration panel. Select the underlying, the index (VolDex®, TailDex®, etc.), the statistic (lifetime percentile or 52-week percentile), and the threshold (e.g., above 90 or below 10). Choose delivery by email or SMS. The engine checks once per day after the closing-level observation is updated and dispatches a notification if the condition is met.

Four key limits: (1) Regime change — historical distributions may not reflect the current market structure; (2) Look-ahead bias — using full-archive statistics to "predict" within the archive is circular; (3) Overlapping observations — at long forward horizons, overlapping windows overstate the independent sample count; (4) Data revisions — the archive is periodically updated, so old downloads may differ slightly from current data. Present historical studies as descriptive, not as forward performance estimates.

The archive covers all tracked underlyings: the core ETFs (SPY, QQQ, IWM, TLT, GLD, and others) available from ETF Analytics, plus the largest, highest-option-volume U.S. single names available on ETF + Equities — technology, financials, energy, consumer, and other sectors. The full current list of tracked underlyings is displayed in the platform's underlying selector.