Emission schedules: why coins halve, decay, or never stop
The block reward is a coin's printing press, and the schedule is its blueprint. The four design choices every schedule makes, the halving math on paper, and the blocks-vs-days trap hiding in every "per year" claim.
Why schedules taper at all
Why not pay 100 coins per block forever? Two forces pull against flat emission. Scarcity: never-slowing supply dilutes holders forever and kills the "last coin mined" story that anchors store-of-value arguments. Bootstrap economics: young networks need generous rewards to attract hashrate before the coin is worth much — pay generously when security is hardest to buy, taper when it isn't.
And one force pulls back: the block reward *is* the security budget — the income paying miners to defend the chain. Taper to zero and eventually someone must pay for security another way (transaction fees, hopefully). Scarcity versus security is the tension every schedule resolves in its own shape.
Four design choices, five shapes
| Choice | Options |
|---|---|
| Step size | ÷2 (halving) · ÷√2 · continuous decay curve |
| Step frequency | per era (years) · yearly · every block |
| Endpoint | zero · small perpetual tail · flat forever |
| Cap | hard cap · asymptote · none |
Bitcoin picked ÷2 every four years to zero with a hard cap. Filling the grid differently gives the other familiar shapes: smooth decay to a cap (no halving day, ever), halvings plus a perpetual tail (the Dogecoin model), decay landing on a small tail, or many small steps — yearly staircases — instead of rare big ones. Each shape sets the coin's psychology as much as its math: dated tradeable events, or their deliberate absence.
Halvings, worked on paper
Take a generic coin: 100 coins per block, halving every 100,000 blocks, one block per minute. Era one pays 100 × 100,000 = 10,000,000 coins in ~69 days. Era two pays 5,000,000, era three 2,500,000, and the whole geometric series converges on 40 million — first era × 2, always. Each halving cuts miner income overnight by half and future dilution by half too; the day it lands is the one date on everyone's calendar.
Blocks, not days
Every schedule is denominated per *block*; what you feel is per *day*, and the conversion runs through block time: daily emission = reward × 86,400 ÷ block-time-seconds. A "60-second" chain running 80-second blocks emits 25% less per day than its docs imply — same schedule, different reality. Likewise a "yearly" halving defined as 525,600 blocks is a calendar year only at exactly 60-second blocks. Whenever you see a daily emission or a halving date, check whether the writer divided by the target block time or the measured one.
See it live on pow.family
The tracked set covers every shape in this lesson — halvings+tail, smooth decay to cap, decay to small tail, yearly staircases. Each project page states its constants under Tokenomics, and the Supply card shows issued supply against the cap or current era.