The mining difficulty of the network dropped by 27.9% as the Bitcoin network adjusted to the massive drop in hash rate. This represents the biggest drop in mining difficulty since the network went live in 2009.
The Bitcoin network updates its mining difficulty level every 2,016 blocks, roughly every two weeks. This is designed to ensure that blocks are produced every ten minutes despite a fluctuating hash rate.
Since the previous adjustment on June 13, Bitcoin’s seven-day moving average hashrate has dropped from 136.47 EH/s to 85 EH/s. This means a 35% decrease.
This was largely due to pressures on Bitcoin mining in China, causing the hash rate to migrate as operations seek mining-friendly sites elsewhere. This record drop came at a much higher rate than anticipated a week ago.
This low hashrate resulted in a slower block generation rate as the remaining hashrate could not keep up with the high difficulty level. Over the past two weeks, on average, a block has been produced almost every 13.9 minutes. This is a much higher time frame than it should be.
In fact, on July 1, it took 129 minutes to form a block. This has been the longest time to create a block since 2011. However, it is worth noting that multiple factors come into play here, including the natural variance in block times.