Bitcoin’s mining difficulty saw its second largest decline on record on December 3, which pushes Bitcoin mining breakeven price lower and brings a little relief to the suffering crypto miners.

Data from major Chinese mining pool BTC.com shows a 15.13 percent decline in bitcoin’s mining difficulty .Mining difficulty is defined as a measure of how hard it is for miners to generate a new block, and Bitcoin’s hashing difficulty algorithm is normally adjusted every two weeks to maintain the normal 10-minute block time.

The sharp drop in mining difficulty makes it easier to mine the world’s leading cryptocurrency and some miners who suffer poor or no profitability amid low bitcoin prices resume their operations.

Mao Shixing, founder of F2pool, the world’s fourth largest bitcoin mining pool, said on Weibo on November 4 that bitcoin’s mining difficulty was adjusted by 15% on Monday, the biggest drop since the launch of AISC miners in 2013. Miners could happily restart their rigs.

Besides, he published the latest list of the “shutdown price” at which the mining of cryptocurrencies becomes unprofitable. According to the infographic, if mining rigs operate at an average power cost of 0.4 yuan per kWh and Bitcoin price drops below 22,438 yuan (about $3,260), this would mean that mining BTC on a Antminer S9 would be unprofitable.

As Bitcoin declines to $3,858 at press time, four types of mining machines, including Antminer T9, S7, Avalon 741 and M3 have already reached the “shutdown price”. Mao said in a recent interview that more than 800,000 miners have shut down their operations since the start of the mid-November price plunge.

Data from BTC.com also indicates that the next difficulty adjustment which will occur in 12 days is expected to see another 16 percent decline. But some analysts think the figure is not accurate, and the difficulty will increase if a large number of mining machines restart operations.