A Year of Transaction Fees
This blog reviews the full year 2021 for transaction fees on Qtum Mainnet.
Block rewards for staking wallets or delegating addresses consist of two parts:
- The “subsidy” of newly-minted QTUM
- The transaction fees and gas
In 2021 the subsidy dropped from 4.0 QTUM to 1.0 QTUM with the hard fork to 32-second blocks, and then to 0.5 QTUM with the halving on December 1, 2021.
The data set for this report consists of blocks 764,515 to 1,508,489 covering January 1, 2021, to December 31, 2021. For each block’s block reward, the subsidy was subtracted leaving the fees paid for the various transactions in that block. Smart contract transactions typically pay gas above the requirements for the smart contract execution, and any excess is refunded in that the same block which executes that smart contract call, leaving a net gas payment to the staker.
Monthly Fees
The chart of monthly fees shows an average of 373 QTUM in fees (approximately 12.4 QTUM per day), not including February, which had fees of 4,109 QTUM due to airdrops.
February 2021 was a lucrative month for the stakers who receive the fees in their block rewards. If we look at a chart of the top 10 blocks by fee, they all occur in February, when there was airdrop activity related to the QiSwap project.
Example Fees
We wrap up by looking at some transactions and blocks to show examples of fees, going from the smallest fee to the largest for 2021.
- The smallest transaction fee for a block was from this SegWit transaction in block 773,604. SegWit transactions are smaller and pay fewer fees, and this transaction paid a fee of 0.00049601 QTUM. If a block holds no transaction, it will have no fees and will pay the subsidy only.
2. A more typical block fee is for a single “Legacy” address coin transfer, for example this transaction in block 787,834, which paid a fee of 0.000904 QTUM.
3. Adding gas for smart contract calls gives larger fees. Block 830,451, which has an offline staking address delegation transaction, had a fee of 0.875 QTUM. Notice the Size (rawtx) of the transaction is larger than the coin transfers above leading to higher fees, plus the transaction pays gas for the smart contract operation. The value of 0.1268 QTUM is the unused gas refund sent back to the delegating address.
4. The largest block fee of the year was for block 795,639, which held 17 smart contract calls for an airdrop, with a fee of 18.4314 QTUM. The reward shown includes the subsidy of 4.0 QTUM.
References
Jackson Blog List — 4+ years of Qtum Technology blogs https://blog.qtum.org/jackson-blog-list-2ecc641a094b