CERM: Coin Emission Rate Modulation
(CERM v0.1 in Bitmark v0.9.7)
Introduction
Most cryptocurrency emission schedules are based on Bitcoin's model, where the block reward reduces over time. In Bitcoin, this "halving" occurs approximately every four years; for instance, the initial 50 BTC reward was halved to 25 BTC, then to 12.5 BTC, and so on.
Bitmark evolved this scheme by adopting intermediate "quartering" steps between halvings. The reward schedule was designed with both halvings {20, 10, 5, 2.5, ...} and intermediate quarterings {15, 7.5, 3.75, ...}.
This results in a smoother emission curve, with the complete sequence of rewards being:
{20, 15, 10, 7.5, 5, 3.75, 2.5, 1.25, ...}
Abstract
Bitmark introduces Coin Emission Rate Modulation (CERM), a dynamic algorithm that adjusts block rewards based on network hash rate conditions. Unlike fixed emission schedules, CERM ties rewards to the health and activity of the network, ensuring sustainable issuance over time while preserving the original total supply cap.
The algorithm compares the average hash rate of the most recent day to the highest daily average observed over the past year. This ratio, known as the Emission Scaling Factor (ESF), determines whether blocks receive the full nominal reward or a reduced amount. Rewards can scale down proportionally but never fall below 50% of the nominal reward, guaranteeing a minimum emission floor.
Emission Cap and Supply
A core principle of Bitmark's economic model is its fixed supply. The absolute emission cap of 27,580,000 BTMK has always been respected and remains unchanged by the CERM algorithm. CERM only affects the *rate* of emission, not the total number of coins that will ever exist.
Live Supply Calculation
0) { // Calculate the amount of BTMK yet to be mined $btmk_yet_to_be_mined = ABSOLUTE_CAP - $btmk_money_supply; // Display the formatted numbers echo "Current Mined Supply:
" . number_format($btmk_money_supply, 8) . " BTMK
Remaining to be Mined:
" . number_format($btmk_yet_to_be_mined, 8) . " BTMK
Error: Could not parse the money supply value from the data file.
"; } } else { echo "Error: The data file appears to be empty.
"; } } else { // Display an error message if the file cannot be read echo "Error: Could not read the money supply data file. Ensure 'BTMK_money_supply.txt' exists and is readable.
"; } ?>How It Works
The values shown are calculated in real-time. The script reads the most recent entry from a local data file and subtracts this number from the fixed total supply cap to determine how many coins are left to be mined.
Concept and Rationale
The main idea behind CERM is to periodically adjust the rate of coin emission to match network demand. Since demand cannot be measured directly, the closest intrinsic blockchain analog is hashrate.
High Hashrate
A higher hashrate signifies that more miners are active because there is high demand for the coin. In this state, coin emission should be high to meet this demand.
Low Hashrate
A lower hashrate suggests lower demand. The emission rate should decrease to avoid flooding exchanges with coins that could depress the price.
Overview of the Mechanism
CERM v1.0 works by scaling half of the nominal epoch reward according to the Emission Scaling Factor (ESF):
ESF = current_hashrate / peak_hashrate
Every 720 blocks (approximately one day), the algorithm performs the following check for each of the 8 mining algorithms:
- It examines the daily average hashrate figures from the past 365 days and selects the single highest value. This becomes the peak_hashrate.
- It defines the average hash rate of the just-completed day as the current_hashrate.
Result: If current_hashrate is lower than peak_hashrate, the reward is proportionally scaled down. However, the scaling only applies to 50% of the reward, guaranteeing that miners always receive at least half of the nominal amount.
Key Definitions
Block Reward
The number of new coins emitted in a block.
Nominal Block Reward
The baseline block reward for an era, before CERM adjustments.
Peak Hashrate
The highest average daily hash rate observed over the past year (365 days).
Current Hashrate
The average hash rate from the just-completed day (720 blocks).
ESF (Emission Scaling Factor)
Ensures rewards scale dynamically with network strength. (Formerly called Subsidy Scaling Factor, SSF).
Epoch (Era)
A period defined by a number of blocks where a nominal reward applies. Under CERM, an era may be extended if rewards are reduced.
