Cryptocurrency miner stocks like Riot Blockchain (NASDAQ:RIOT), Marathon Digital (NASDAQ:MARA) and Bit Digital (NASDAQ:BTBT) are tumbling in Monday morning trading, as speculators shy away from bitcoin (BTC-USD) and other major digital tokens in the wake of a broader selloff in risk assets. The global crypto market cap is standing at $1.50T at the time of writing, off a whopping 50% from its peak in November. Bitcoin (BTC-USD -5.6%) is plunging to $32.6K over the past 24 hours and ethereum (ETH-USD -5.5%) is dropping to sub $2.4K. At a time when a slew of central banks pivot to tighter monetary policy to tame persistently high inflation, "most investors have taken a risk-off approach -- selling stocks and cryptos alike in order to cut down risk,” said Darshan Bathija, chief executive crypto exchange Vauld, as quoted by Bloomberg. Recall in the week ended May 6 when the Federal Reserve hiked the target rate by