If you think oil had a rough 2014, consider bitcoin. The digital currency has plunged 54 percent since the beginning of the year. By contrast, Brent crude has fallen 44 percent; the ruble is off some 46 percent against the dollar.

Bitcoin’s collapse comes as governments around the world consider regulating or prohibiting the virtual currency to prevent criminals from using it to trade contraband. Meanwhile, bitcoin is facing competition from a slew of rivals striving to be more palatable to regulators.

The dramatic reversal -- bitcoin reached more than $1,100 in 2013 and is now trading at about $350 -- is prompting told- you-sos from skeptics who long said the currency’s promise was overhyped.

“I don’t know that it’s on its last legs, but it’s not looking good,” said Nathalie Reinelt, an analyst at financial consulting firm Aite Group, who has written reports expressing doubts that bitcoin will become a mainstream currency. “It’s not in a healthy state.”

There are still plenty of bitcoin diehards out there. Silicon Valley investor Tim Draper remains a booster. Conferences devoted to the so-called cryptocurrency are attracting droves of adherents. Venture capital firms are funding bitcoin-related startups. Companies from Microsoft Corp. to Overstock.com Inc. accept bitcoin as payment.

Bitcoin proponents like the relative anonymity afforded by the virtual currency. Because users can register for bitcoin wallets without disclosing their identity, they can buy and sell stuff without the government looking over their shoulder.

Bitcoin Ban

Regulation could end that. A proposal under consideration in New York State, for example, would require companies that store or exchange virtual currencies to obtain licenses and verify customers’ identities and addresses. Ukraine has banned bitcoin altogether, China has prohibited banks from clearing bitcoin transactions and Russia is considering fining users.