According to BlockBeats, on June 20, Bitcoin mining difficulty underwent an adjustment at block height 848,736. The mining difficulty decreased by 0.05% to 83.68 T. The current average network hashrate stands at 598.97 EH/s.

This adjustment in mining difficulty is a part of the Bitcoin network's self-regulating mechanism. It ensures that the time taken to add new blocks to the blockchain remains consistent. The difficulty adjustment occurs approximately every two weeks or after 2,016 blocks have been added to the blockchain.

The decrease in mining difficulty suggests that fewer miners are competing to solve the mathematical problem that allows them to add the next block to the blockchain and claim the block reward. This could be due to a variety of factors, including market conditions, the cost of electricity, and the availability of mining hardware.

The average network hashrate is a measure of the computing power of the Bitcoin network. A higher hashrate indicates a more secure network, as it would require a significant amount of computational power to launch a successful attack. The current average network hashrate of 598.97 EH/s suggests that the Bitcoin network remains robust and secure.