Definition. This chart applies a 2-year rolling Z-Score to the percent of Bitcoin miner revenue derived from transaction fees — fees divided by fees plus newly minted coins — providing a statistical measurement of on-chain congestion and fee-market pressure relative to protocol issuance. Positive readings are shown as red columns 🔴 and negative readings as blue columns 🔵, with price in black.

Technical. The Z-Score normalizes the daily fee share of revenue (7-day SMA) against its own trailing distribution:

• Fee Share = Fee Revenue / (Fee Revenue + Block Subsidy)
• Z-Score = (Fee Share - sma(Fee Share, 2yr)) / std(Fee Share, 2yr)

The result is split around zero into the positive 🔴 and negative 🔵 column traces.

Interpretation. Periods of high network activity and blockspace congestion push transaction fees up faster than issuance, lifting the fee share of miner revenue. The Z-Score expresses today's fee share in units of standard deviations from its 2-year norm:

• Elevated Fee Pressure 🔴 will return a positive Z-Score, signalling fees contribute an above average share of miner revenue relative to the last 2 years.

• Low Fee Pressure 🔵 will return a negative Z-Score, signalling fees contribute a below average share of miner revenue relative to the last 2 years.

Sustained elevated readings have historically coincided with bull-market congestion and episodic blockspace demand waves, while long negative stretches are characteristic of quiet bear-market conditions. Because the fee share is heavily right-skewed, upside excursions reach far larger magnitudes than downside ones. Note that halvings mechanically lift the fee share — the subsidy in the denominator halves — so post-halving readings are structurally elevated independent of congestion.

Notes. Built from Percent Miner Revenue from Fees, the share of miner revenue derived from fees rather than the fee amount in BTC or USD. The 2-year window reacts faster than the cycle-spanning variant in Miner Revenue from Fees Z-Score (4 Year); all windows are compared in the Miner Revenue from Fees Z-Score Ribbon.