This specification describes the data as published on Oct 21, 2026, covering 431 funds. Rebuilt every trading night.
Buffer ETF methodology
What is covered, where each figure comes from, how it is worked out, and what it cannot tell you. Check any of it yourself.
Scope
431 defined outcome ETFs from 8 issuers: AllianzIM, Calamos, Corgi, First Trust, Innovator, PGIM, TrueShares, iShares. A fund is covered when its issuer publishes daily outcome-period values for it on a public page. Funds without daily values are left out. ETFIQ does not estimate between filings.
413 of 431 funds carry an SEC series ID and CIK, matched by ticker, then by name, against the SEC series and class file. Tickers are reused after a fund closes, so a ticker alone is not enough.
Sources
Every source behind these figures, what it provides, and how often it is read
| Source | What it provides | Read | Spec |
|---|---|---|---|
| Issuer outcome-period pages | Starting cap, remaining cap, buffer, downside before buffer, period start and end, fund and reference return | Every trading night | · |
| Prospectus supplements (SEC 485BPOS) | Buffer geometry and participation terms at period start | On filing | document ↗ |
| SEC series and class file | Series id and CIK for each fund | Weekly | document ↗ |
| Prospectus XBRL | Expense ratio | Weekly | document ↗ |
Definitions and method
The most the fund can still return from today to the end of its outcome period, after fees. This is the issuer’s remaining cap, in fund-price terms.
How far the fund can fall from today before its buffer starts to absorb losses. This is the issuer’s downside before buffer, in fund-price terms.
How much of the buffer is unused, in index points. If the buffer runs from bstart to bend in reference-return space and the reference has returned R since the period started, the buffer used so far is max(0, min(B, bstart − R)) where B = bstart − bend. Protection left is B minus that. It is in index points, not fund-price points, because the buffer is set on the index.
One axis per fund, from the buffer floor to the cap in reference-return space, with two markers: where the reference index sits and where the fund sits. The same axis for every fund lets you compare funds with different buffers and start dates.
The window over which the issuer’s cap and buffer apply, from period start to period end. Figures mean nothing outside it, so the period dates appear beside every fund.
Each figure is labeled as the issuer’s or ETFIQ’s.
What is checked every night
What this cannot tell you
How to check any of this
Every published figure is free as JSON on the open data page. Use ETFIQ's figures with attribution and the as-of date. Issuer data stays under its owner's terms. Independent code recomputes every number nightly from the raw sources, and the statistics page shows the result. Errors are listed on the corrections page.
A figure marked ETFIQ is one ETFIQ computed. Every other figure is the issuer’s or the exchange’s, and is labeled that way.
Cite this pageCitation, APA and Markdown
ETFIQ, Buffer ETF methodology, data as of Oct 21, 2026. https://etfiq.com/methodology/buffer
ETFIQ. (Oct 21, 2026). Buffer ETF methodology. Retrieved from https://etfiq.com/methodology/buffer
[Buffer ETF methodology (ETFIQ, Oct 21, 2026)](https://etfiq.com/methodology/buffer)
Free to use with attribution for figures ETFIQ computes; issuer data stays under its owner's terms. The underlying files are at Open data.