# AHR999 Dataset — Full Guidance

> Open, daily-updated AHR999 (Bitcoin hoarding / DCA valuation index) dataset,
> self-computed from Binance BTCUSDT daily closes and published as JSON, CSV,
> and a read-only HTTP API. Code is MIT; data is CC BY 4.0.

This file is the long-form companion to https://ahr999.aix4u.com/llms.txt and is
intended for AI agents and crawlers that want the complete contract on one page.

## Canonical URLs

- Homepage (English): https://ahr999.aix4u.com/
- Homepage (Chinese): https://ahr999.aix4u.com/zh/
- Methodology: https://ahr999.aix4u.com/methodology/ (zh: /zh/methodology/)
- Data format: https://ahr999.aix4u.com/data-format/ (zh: /zh/data-format/)
- API reference: https://ahr999.aix4u.com/api/ (zh: /zh/api/)
- FAQ: https://ahr999.aix4u.com/faq/ (zh: /zh/faq/)
- Repository: https://github.com/RuochenLyu/ahr999-dataset

## Data Endpoints

- JSON dataset: https://ahr999.aix4u.com/datasets/ahr999.json
- CSV dataset: https://ahr999.aix4u.com/datasets/ahr999.csv
- OpenAPI 3.1 description: https://ahr999.aix4u.com/openapi.json
- API catalog (linkset): https://ahr999.aix4u.com/.well-known/api-catalog

Both data endpoints are static, read-only, require no key, and respond with
`Access-Control-Allow-Origin: *`. The series changes at most once per day, after
the UTC daily close — cache responses instead of polling.

## What AHR999 Is

AHR999 is a Bitcoin dollar-cost-averaging (DCA) heuristic originally proposed by
the Chinese investor 九神. For each UTC day it multiplies two ratios:

    ahr999 = (close / ma200) * (close / fitted)

where:

- `ma200` is the 200-day simple moving average of the daily close.
- `fitted = 10 ^ (5.84 * log10(coin_age_days) - 17.01)` is a log-log fitted
  "fair value" curve, with `coin_age_days` measured from the BTC genesis block
  date 2009-01-03.

The lower the value, the cheaper BTC is relative to both its recent 200-day cost
basis and its long-run fitted trajectory.

## Field Contract

Each JSON row is one UTC calendar day, ordered oldest first. Fields:

- `date`: UTC date in `YYYY-MM-DD`.
- `close`: BTCUSDT daily close from Binance public market data (USDT per BTC).
- `ma200`: 200-day simple moving average of `close`, or `null` for the first 199
  rows.
- `ahr999`: `(close / ma200) * (close / fitted)`, or `null` when `ma200` is null.
- `quantile5y`: empirical rank of `ahr999` within the active recent window, in
  `[0, 1]`, or `null` until 365 valid AHR observations exist.
- `windowKind`: one of `insufficient_samples`, `expanding`, `rolling_5y`.

In CSV, a `null` is serialized as an empty field.

## Conventional Zones

Folk thresholds shown on dashboards (heuristic, not part of the formal
definition, and not buy/sell signals):

- `< 0.45`: bargain zone (抄底区)
- `0.45` to `< 1.20`: DCA zone (定投区)
- `1.20` to `< 3.00`: caution zone (谨慎区)
- `>= 3.00`: bubble zone (泡沫区)

## Recommended Agent Tasks

- Fetch the latest row: `GET /datasets/ahr999.json`, read the last array item.

      curl -s https://ahr999.aix4u.com/datasets/ahr999.json | jq '.[-1]'

- Load a date range by filtering rows by `date`.

      curl -s https://ahr999.aix4u.com/datasets/ahr999.json \
        | jq '[.[] | select(.date >= "2026-01-01" and .date <= "2026-01-31")]'

- Download the CSV: `curl -O https://ahr999.aix4u.com/datasets/ahr999.csv`
- Explain the field meanings and the calculation method.
- Cite the dataset and license when using or redistributing values.

## Boundaries

- This site is a public read-only dataset and dashboard.
- No authentication, OAuth, accounts, trading, brokerage, payments, or portfolio
  actions are offered or implied.
- AHR999 is a heuristic indicator for research, education, and observability. It
  is not financial advice and does not predict future returns.

## Attribution

Data files are licensed under CC BY 4.0. Cite:

`ahr999-dataset contributors (2026). "ahr999-dataset - open BTC hoarding index computed from Binance BTCUSDT daily closes". https://github.com/RuochenLyu/ahr999-dataset`