Bitcoin miners generated an estimated $328 million in revenue in September, down 11% from August, according to Coin Metrics data analyzed by CoinDesk.
The moderate decrease in revenue came as bitcoin (BTC) stumbled through September, closing the month down 8% after gaining over 25% through July and August.
Revenue estimates assume miners sell their BTC immediately.
Network fees brought in $26 million in September, or just over 8% of total revenue, down 2 percentage points from fees comprising 10% of revenue in August.
Notably, fees as a percentage of total revenue continues a strong upward trend since April after the block subsidy halving in May.
Increases in fee revenue are important to sustain the network’s security as the block reward decreases every four years.
Bitcoin's average transaction fee bounced between $1 and $5 through September.