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Stock-to-Flow API

Bitcoin Stock-to-Flow (S2F) model — quantifies BTC scarcity vs new supply, projecting long-term fair value based on halving cycles.

Webhook URL
https://api.hunchmachine.com/webhook/indicators?indicator=stock_to_flow&api_key=YOUR_API_KEY

Description

Implements the classic Stock-to-Flow model, comparing Bitcoin's existing stock (supply) to annual new issuance (flow). As halvings reduce new supply, the S2F ratio increases, historically coinciding with large bull-cycle expansions. This endpoint provides a programmatic snapshot of where price sits relative to the S2F curve.

What this endpoint provides

Real-time S2F ratio, fair-value estimate, qualitative zone, and narrative summary. Ideal for dashboards or automations that need to discuss long-term scarcity trends without re-implementing the regression logic.

Response fields

btc_price_usd

Latest Bitcoin price (USD).

s2f_ratio

Current Stock-to-Flow ratio (supply divided by annual issuance).

fair_value_usd

Stock-to-Flow fair value price estimate.

zone

Qualitative zone label (e.g., Deep undervaluation vs S2F, Bubble).

zone_score

Numeric score indicating position within the S2F bands.

trend

Directional assessment (up, down, neutral).

momentum_state

Momentum narrative such as strengthening, stable, cooling.

summary

Natural-language summary combining price, ratio, and interpretation.

Output example

[
  {
    "indicator": "stock_to_flow",
    "timestamp": "2025-11-01T03:13:58.207Z",
    "btc_price_usd": 109868,
    "s2f_ratio": 121.42,
    "fair_value_usd": 318767,
    "zone": "🟦 Deep undervaluation vs S2F",
    "zone_score": 1,
    "trend": "up",
    "momentum_state": "strengthening",
    "summary": "BTC $109,868 vs S2F fair value $318,767 → Zone: 🟦 Deep undervaluation vs S2F (score 1)."
  }
]

Interpretation & Use

The Stock-to-Flow model treats Bitcoin as a scarcity-based asset similar to gold or silver, projecting price appreciation as issuance declines. • **Low zone_score (1–3)** → Market trading well below S2F fair value → historically accumulation or undervalued phase. • **Mid zone_score (4–6)** → Near equilibrium with the S2F curve → fair value region. • **High zone_score (7–10)** → Overvaluation vs scarcity → historically near tops. Automations can monitor zone_score or btc_price_usd / fair_value_usd ratio to classify valuation regimes, while the zone label provides immediate interpretability for dashboards or LLM-based reasoning about cycle positioning.