Coin Emission Rate Modulation
Bitmark is a decentralized Level-1 (L1) blockchain that uses 8 different proof-of-work (PoW) algorithms to secure its network and verify transactions. Miners who contribute computing power to validate transactions and add new blocks to the blockchain are rewarded with Bitmark coins.
1st epoch, 20 tokens per block
2nd epoch, 15 tokens per block (first quartering)
3rd epoch, 10 tokens per block (first halving)
4th epoch, 7.5 tokens per block (second quartering)
5th epoch, 5 tokens per block (second halving)
6th epoch, 3.75 tokens per block (third quartering)
7th epoch, 2.5 tokens per block (third halving)
8th epoch, 1.875 tokens per block (fourth quartering)
9th epoch, 1.25 tokens per block (fourth halving)
On June 6th, 2018, the Bitmark community made three major changes:
The CERM algorithm adjusts block rewards by comparing current hash rate to peak hash rate (the highest daily hash rate in the past year). This results in an emission scaling factor (ESF) that determines whether the block reward is given in full or reduced proportionally. If the current hash rate is at or above the peak, the full block reward is given. If it’s below the peak, the reward is reduced, but at least half of the total reward is always given.
Each PoW algorithm operates independently and rewards are set for each without regard to the other algorithms. This means that emission thresholds and epoch changes will happen at different times for each algorithm. The current hash rate is calculated based on the previous 90 blocks for each algorithm, and the peak hash rate is determined by looking back at the previous 32,850 blocks (representing one year of data).
Coin Emission-Rate Modulation adjusts how quickly new Bitmark is issued. It does not increase the maximum emission limit of 27,580,000 BTMK. Modulation means adjusting or controlling the rate: when rewards are reduced, fewer coins are issued per block.
The Emission Scaling Factor (ESF) compares current average hashrate with the reference peak hashrate:
ESF = current_hashrate / peak_hashrateThe reference peak is the highest average hashrate in the preceding year’s block-based history. When current hashrate reaches that peak, miners receive the full nominal reward for their emission epoch. Below the peak, CERM scales half of the nominal reward while leaving the other half unchanged, so the reward does not fall below half the nominal amount.
For example, with a nominal reward of 5 BTMK and an ESF of 0.5, the unchanged half is 2.5 BTMK and the scaled half is 1.25 BTMK, giving an illustrative reward of 3.75 BTMK.
The Chainetics overview describes a nominal day as 720 network blocks. In Bitmark’s eight-algorithm implementation, each algorithm recalculates its scaling factor every 90 of its own blocks, approximately one day at the target block spacing. It compares the latest period with up to 365 such periods of history: 32,850 blocks for that algorithm. These are block-based intervals; their elapsed time can vary.
Each algorithm has its own hashrate history, reward modulation, and emission state. Different algorithms can therefore have different rewards and reach their emission thresholds at different times.
Read more: Chainetics CERM overview · Bitmark’s published reward-modulation documentation.