Stock-to-Flow Model

The Stock-to-Flow model was published in March 2019 by the pseudonymous analyst PlanB in "Modeling Bitcoin Value with Scarcity." S2F = existing stock ÷ annual new production — roughly 60 for gold, doubling for Bitcoin at each halving. Regressing market cap on S2F over history, the model claimed a power-law fit (R² ≈ 0.95) and projected price targets for each post-halving epoch.

Through 2019–2021 the model drew a huge following, with price broadly inside the model band before 2021. Its post-2021 projections failed decisively — the ~$100K-scale targets for that epoch never printed within the cycle, and price ran persistently below the band. Nor was the critique hindsight: Strix Leviathan showed in 2019 that across 115 years of gold data, the same S2F value of 60 coexisted with market caps from ~$60 billion to ~$9 trillion — the single-variable scarcity premise fails on its own reference asset.

Three main statistical criticisms. Market cap equals stock × price while S2F's numerator is also stock — the regression shares a variable across both sides, inviting tautology (Bitcoin Magazine ran a piece calling it statistically invalid). The cointegration evidence once cited in support was later disputed (Eric Wall catalogued the reversals). And the model is supply-only — demand appears nowhere.

S2F is the best case study of how the halving narrative shapes market expectations — a large share of participants once priced against it, making the model itself part of the market. Today it serves better as a specimen of financial sociology and scarcity narratives than as a valuation tool. The curve on this page is provided for historical reference.

Beyond cycle positioning, gauge short-term sentiment with market-wide liquidations and BTC liquidation data.