Bitcoin stock‑to‑flow model 2025 review – scarcity metric after 2024

Bitcoin’s stock‑to‑flow (S2F) ratio surged past 120 following the April 2024 halving, while the market price broke the $100,000 barrier for the first time, reigniting debate over the model’s predictive power versus its historical misses【1†L31-L38】【2†L13-L20】.

Model origins and early success

PlanB introduced the Bitcoin S2F model in March 2019, regressing market cap against the scarcity metric and reporting an R‑squared of 0.94‑0.95, implying that over 94 % of price variance was explained by supply scarcity alone【1†L15-L22】【2†L7-L9】. The framework gained traction because Bitcoin’s halving schedule—reducing new issuance every four years—creates predictable jumps in the S2F ratio: from ~11 pre‑2012, to ~25 after 2016, to ~56 post‑2020, and finally above 100 after the 2024 event【1†L27-L33】. This scarcity narrative matched gold’s S2F of ~60, bolstering the view that Bitcoin could become a “digital gold.”

Where the model fell short

The original S2F forecast projected $100,000‑$288,000 by the end of the 2020‑2024 cycle, yet Bitcoin peaked at $69,000 in November 2021 and then slumped to roughly $16,000 by late 2022—far below the model’s target【1†L41-L45】【2†L13-L16】. Analysts note the model’s omission of demand factors; the 2022 price collapse coincided with higher rates, the Terra/LUNA crash, and the FTX fallout, none of which the S2F equation accounts for【1†L49-L53】. Statistical critiques also flag spurious correlation and over‑fitting, given that both price and S2F are upward‑trending series【1†L55-L58】.

2024‑2025 performance snapshot

The April 2024 halving halved the block reward from 6.25 to 3.125 BTC, pushing the S2F ratio from ~57 to ~120 and theoretically making Bitcoin the most scarce tradable asset【2†L13-L15】. Prices responded with a new all‑time high above $100,000 in 2024, aligning with the model’s directional premise that halvings precede bull runs. However, the specific price targets of $200,000‑$500,000 for this cycle remain unmet, with Bitcoin trading around $126,000 in October 2025—still less than half of the S2FX projection of $288,000【1†L61-L66】【2†L13-L16】.

What to watch

• Next halving countdown – the subsequent halving is expected in 2028; S2F ratio will rise further, potentially intensifying scarcity‑driven price narratives.
• Price resistance at $150,000 – breaking this level would bring the market closer to the lower bound of the 2024‑2025 forecast range.
• On‑chain flow metrics – monitor daily new‑coin issuance; a sustained drop below 400 BTC/day could reinforce scarcity arguments.

The S2F model remains a useful lens for Bitcoin’s supply dynamics, yet its track record as a price predictor is mixed. As the next halving approaches, the key question is whether scarcity alone will drive Bitcoin toward the higher valuation tiers or if demand‑side shocks will continue to dominate price movements.