Staking yield is not a fixed interest rate — it is the residual of protocol issuance minus the costs and penalties borne by validators. On Ethereum post-Merge, issuance is roughly ~2.6 ETH per epoch distributed across ~1,000,000 active validators, so per-validator income scales inversely with total stake. A validator's gross APR ≈ (issuance × your effective balance) / total staked, then reduced by MEV, tips, and penalties.

Three forces shape net validator returns:

Issuance — base protocol reward, falls as total ETH staked rises.
Priority fees & MEV — variable, often 20–40% of gross rewards in busy markets.
Penalties & slashing — inactivity leaks (small, continuous) vs. slashing (1 ETH minimum, up to full balance for correlated faults).

Component	Typical share of gross	Volatility
Issuance	60–75%	Low
Priority fees	10–20%	High
MEV (via relays)	10–25%	High
Penalties	−1 to −5%	Medium