The BTC NHCI track record is a public, tamper-evident ledger of the daily Bitcoin cycle score. Each day the NHCI - a 0-100 index built from 37 on-chain, macro, and market indicators - is recorded with its cycle phase and sealed into a SHA-256 hash-chain. A 10-year point-in-time backtest identified 8 of 8 major Bitcoin turning points (4 cycle tops, 4 cycle bottoms). From the seal date forward, one new reading is hash-chained and published every day as a live, verifiable record.
Every entry hashes the one before it, so editing any past day breaks every later hash. Anyone can download the raw ledger and recompute the whole chain to confirm the published head hash - in any programming language, with no account, no API key, and no access to the formula. The canonical string is deliberately trivial to reimplement: sha256(seq|date|score|phase|band|version|source|prev_hash). The ledger is published as raw data anyone can fetch and re-hash. A public timestamped mirror - a dedicated ledger repository and an on-chain Solana anchor - is the next layer, adding an external, trustless timestamp on top of the hash-chain.
We keep this honest. The 10-year 8-of-8 is a point-in-time backtest: 3,650 daily readings reconstructed under the current v3.2 methodology, with no hindsight in the inputs. It is not a claim of live calls made in 2017. The live forward record - the entries appended and git-committed each day - began at the seal date and is the real-time track record that compounds going forward.
Nothing breaks, and nothing is quietly rewritten. Every entry is stamped with the exact methodology version that produced it. When the version is upgraded, past entries stay frozen at their version and a new version block opens with its own effective-from date - the hash-chain continues unbroken across the boundary. The record can never be improved with hindsight.
The NHCI is a single 0-100 read on where Bitcoin sits in its market cycle. Lower is colder (undervaluation), higher is hotter (cycle-top risk):
The ledger publishes these outcomes - the score, the phase, the seal - but never the formula: the 37-indicator weighting stays proprietary. Transparency of results, not of the recipe.