US Equities Detailed Adjustment Factors

How to use it

Rows are effective-dated. Answer point-in-time questions with the row in force on the as-of date, never the latest row. SecId and ASID are both durable AlgoSeek security keys but different values (the ASID lookup links them); tickers are reused across companies, so resolve a ticker to a key with a trade date.

Typical use

Point-in-time security identity, corporate-action adjustment, and universe construction for US equities.

Limitations

Vendor-curated reference data: rows can be restated when AlgoSeek learns of a late or corrected event, so land each delivery as a snapshot rather than overwriting history. AdjustmentFactor is a multiplicative per-event ratio. Backward adjustment (anchored on the latest date): a price dated D is multiplied by the product of the AdjustmentFactor of every event whose EffectiveDate is later than D; prices on or after the latest EffectiveDate use AF=1. An event therefore changes only dates strictly before its EffectiveDate. Guide worked example (formulas are images in the PDF), AAPL 2014 with f1=0.995050548 (20140807 CashDiv), f2=0.142857143 (20140609 BonusSame), f3=0.994445664 (20140508 CashDiv): prices from 20140807 use AF=1; 20140609-20140806 use f1 (0.99505); 20140508-20140608 use f1*f2 (0.14215); earlier dates use f1*f2*f3 (0.14136). Volume is DIVIDED by the corresponding cumulative factor, and only events with Affects Volume = Yes enter that product (BonusSame, CapReduct, Cons, ScriptDiv, SecSwap, Reclass, Subdiv). In the guide example only the 20140609 BonusSame touches volume, so volumes before 20140609 are divided by 0.142857143 (x7) and later volumes by 1. Price-only reasons (CashDiv, Distrib, DeMerg, rights, etc.) must not be applied to volume. Forward adjustment is said to be possible ('forward- or backward-adjusted pricing') but this guide only walks through the backward procedure; the Cumulative Adjustment Factors dataset publishes ready-made forward factors.

Coverage

All US exchange-listed equities (stocks, ETFs, ETNs, ADRs, preferred stock, warrants and similar), events from 2007 to present. Sample is AAPL only (32 events, 20120809-20200207).

Usage constraints

• Licensed vendor data: never export raw rows to a tenant-local destination or include them verbatim in a public artifact; serve only through entitlement-checked platform reads.
• Do not treat the vendor's `Ticker` as a stable identity across time; join on an AlgoSeek security key (SecId or ASID, which are distinct) or the platform symbol mapping.

Known issues (8)

• Update cadence and publication latency are not stated in the guide; confirm with AlgoSeek (or GET /v1/meta/datasets/{id}/status).
• Documentation discrepancyGuide text says rows correspond to 'individual bars' (boilerplate from price guides); rows are corporate-event records.
• Documentation discrepancyIn the Detailed guide the Adjustment Reason table (Table 3) is garbled by plain text extraction (price/volume columns interleaved); reading it with table-aware extraction gives exactly the same 18 reasons and Yes/No flags as the Basic guide.
• Documentation discrepancyGuide Table 1 prints ReportDate = EffectiveDate for the 2014 events shown; in the sample ReportDate is later than EffectiveDate for the first three rows (20130208 for events effective 20120809, 20121107 and 20130207) and carries _02/_03/_04 suffixes from 20180511 onward.
• Documentation discrepancyGuide's Detail example for a split says 'Subdivision of 2 for 1' means holders receive two ADDITIONAL shares per share held, which reads as a 3-for-1; the standard reading of 2-for-1 is one additional share. The sample's 'Bonus of 6 ... for 1' has factor 1/7 (six additional shares). Do not derive factors from Detail text; use AdjustmentFactor.
• Documentation discrepancyGuide's Detail example for a demerger ends with ',US03965L1008' after the bracket tokens, a trailing ISIN that the sample rows (dividends and one bonus) do not show.
• Documentation discrepancySample is a 32-row AAPL extract ending 20200207 (CashDiv 31, BonusSame 1) and omits the 20200831 Subdiv shown in the Cumulative sample, so it is truncated.
• Documentation discrepancyTradedate aggregation wording is ambiguous: 'one CSV file with data per symbol per effective date' versus the example of all events on one date in a separate file.