Internet users noticed a significant reduction in transaction fees in the bitcoin network.
With $30-40 in early January the fee for confirmation in the next block dropped to $0,25.
Mempool transaction also greatly relieved to 36 MB. A week ago the volume of unconfirmed transactions was 140 MB.
The possible reasons are depreciation of bitcoin and the number of spam transactions, as evidenced by the decrease in Nampula.