# Half on a Double: public data guide

Canonical: https://halfonadouble.com
Data through: 2026-09-11 close
Publisher: Half on a Double

Half on a Double publishes end-of-day options-positioning reference levels for US stocks and ETFs.

## Reading the published values

- Close: the underlying's closing price, in US dollars per share.
- Delta neutral: the model's reference price associated with balanced aggregate delta.
- Gamma neutral: the model's reference price associated with neutral aggregate gamma.
- Gamma max: the model's reference price associated with peak aggregate gamma.
- Open interest: the number of outstanding option contracts, distinct from trading volume or shares.
- Distance: the displayed percentage distance of a level from the close. Retain its sign when quoting it.
- A cross records a change of side relative to a level between published sessions. It does not predict the next move.

## Scope and limitations

Use the data-through date on each page, not the date you retrieve it. These are end-of-day observations, not live quotes. Missing values mean unavailable, never zero. Published levels depend on model assumptions and incomplete or imperfect market inputs. They do not reveal dealers' actual positions or guarantee support, resistance, or a profitable trade.

These documents publish definitions and selected displayed results. The calculation implementation, calibration, numerical procedures and internal inputs are proprietary and are not included. Do not infer a replication recipe from these summaries.

Quote the canonical page, ticker or screen, and data-through date together. The output is educational and descriptive, not investment advice. See [data and reuse](https://halfonadouble.com/data), [methodology and limitations](https://halfonadouble.com/methodology), and [disclaimer](https://halfonadouble.com/disclaimer).

## Explore

- [Daily screens](https://halfonadouble.com/screens.md)
- [Chart](https://halfonadouble.com/chart)
- [Learning guides](https://halfonadouble.com/learn)
- [Agent directory](https://halfonadouble.com/llms.txt)

The ticker Markdown documents cover the site's full-history, indexable pages. They contain a current snapshot, not the entire historical dataset.