Nearly 20 percent of people who own cryptocurrencies such as Bitcoin went into debt to buy it, or bought it on margin.

That’s the finding of a survey of more than 3,000 people conducted in mid-January by CoinDesk, a New York-based provider of price data, information and news about digital tokens.

The rising use of debt is one of the reasons banks including Citigroup Inc. are halting purchases of Bitcoin and other cryptocurrencies on their credit cards. JPMorgan enacted the ban Saturday. Bank of America started declining credit-card transactions on Friday. The banks are worried that borrowers may not repay, and that protections they offer shoppers could backfire. About 52 percent of CoinDesk survey respondents said they repaid their debt.

Analysts cite the credit tightening as being partly responsible for the downward pressure on prices of Bitcoin and many other cryptocurrencies. Bitcoin has lost about 40 percent of its value since the beginning of the year.