The DARI (Difficulty Adjusted Reward Index) is a way to compare the rewards of two chains that share the same reward system. The following calculation is used to determine the DARI:
(block coinbase+fees in satoshis) / (block difficulty) * (exchange rate in USD)
With this result we can compare the two chains. For example, using the DARI of the last block we can estimate that a BCH miner could potentially collect (9.21 / 7.90 =) 1.17 times the reward (in USD) that a BTC miner could collect.
Reward
Fees
Inflation
Difficulty
and many others here https://fork.lol/
Why they take fee to mine btc
hi, pools generally request you for fees as support your mining