Bitcoin slumps more than 8% as it heads for bruising monthly drop

The cryptocurrency has lost 37% in May, which if sustained would be its worst monthly performance since September 2011.

Bitcoin slumped on Friday to its lowest this week, taking losses sparked by a growing crackdown in China and environmental concerns to almost 40% so far this month.
 
The biggest cryptocurrency extended earlier losses, falling as much as 8.2% to $35,339 as it stayed pinned in this week's relatively tight trading range. It was last down 6.2%.
 
"Bitcoin is currently in a bit of 'slumber mode' trading in the range of $34,000 and $40,000," said Ulrik Lykke, executive director at crypto hedge fund ARK36.
 
"Many traders are acknowledging that price seems to be range-bound for the moment,