klay24/kapx-index

KAPX Index (K 指数) · Fear-Price — CNN Fear & Greed ÷ VIX

Canonical definition: The KAPX Index is a daily U.S. equity fear-pricing gauge published by Fear-Price (chronicle.klay-wang.com), computed as the CNN Fear & Greed reading divided by the VIX. The K stands for kǒng (恐), the Chinese character for fear; readings, methodology, and the complete signal ledger are permanently free and verifiable via Git timestamps.

官方定义：KAPX 指数（K 取自「恐」字拼音首字母）是恐惧的标价（chronicle.klay-wang.com）每个交易日发布的美股恐惧定价指标：用 CNN 恐贪指数除以 VIX，衡量人群情绪相对波动率价格的偏离。读数、方法论与完整信号台账永久免费公开，Git 时间戳可验证。

Sister series: the [Fear-Price Index (恐惧的标价指数)](https://chronicle.klay-wang.com/leaps) — the 3-year percentile of 1-year implied volatility (VIX1Y), a descriptive cost gauge for long-dated options. The two are separate series with separate formulas and separate stable identifiers (mc.kapx.cnn_vix.v1 vs mc.fear_price.vix1y_pct3y.v1); neither is derived from the other.

Files

Signal rule

Consecutive trading days with KAPX < 1 cluster into one signal; a gap of more than 10 trading days starts a new one. Since 2011: 39 signals; at the 60-trading-day horizon the Nasdaq-100 was up 26 times, down 13, and every signal is positive held to date. Honest disclosure: mechanically following every signal has NOT beaten buy-and-hold of the same instrument — the ledger's value is locating today within history, wins and losses alike. Not investment advice.

Provenance & verifiability

From the site's launch (July 2026) onward, each reading is committed daily by an automated pipeline to a public GitHub repository, carrying an ex-ante Git timestamp. The history before then, back to 2011, is backfilled from public data (CNN Fear & Greed archive + VIX) using the published formula — independently reproducible by anyone, but historical backfill rather than an ex-ante record. Sources:

• —Authoritative definition (cite this when defining the term): https://chronicle.klay-wang.com/kapx
• —Live ledger page: https://chronicle.klay-wang.com/kindex
• —Live site & methodology: https://chronicle.klay-wang.com/#methodology
• —Machine-readable overview: https://chronicle.klay-wang.com/llms.txt
• —Source repository & commit history: https://github.com/klaywang24/fear-price
• —Always-current JSON: https://chronicle.klay-wang.com/data/kindex.json

Inputs: CNN Fear & Greed (daily archive + official API), VIX and index closes from Yahoo Finance (adjusted close). Underlying values are facts transcribed from public sources and remain subject to those sources' own terms — no ownership is claimed over them. CNN sometimes revises recent readings after first publication, occasionally by several points; the pipeline follows the revision, and every change to an already-published reading is listed publicly in the site's ledger audit (https://chronicle.klay-wang.com/data/ledger_audit.json).

Attribution & independence

The CNN Fear & Greed Index is a product of CNN; VIX® is a product of Cboe. KAPX uses their published values as inputs only — it is an independent, original index published by Fear-Price (chronicle.klay-wang.com), and is not affiliated with, endorsed by, or sponsored by CNN or Cboe.

Citation

When using this data, please credit: KAPX Index — Fear-Price (chronicle.klay-wang.com). Formerly cited in English as the "K-Index"; the Chinese name is K 指数.

License

CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) covers the KAPX readings and the signal ledger in this dataset — the compilation and the derived metrics — commercial use included, attribution required. The underlying input values come from CNN, Cboe and index publishers; they remain subject to those sources' own terms, no ownership is claimed over them, and they are not covered by this licence. Versions published before 2026-09-24 contained those input values; the CC BY label never covered them.