The majority of Circle’s USDC stablecoin is backed by U.S. dollars, the company revealed on Tuesday.

Circle, a global payments company, was one of USDC’s creators. It published a breakdown of its assets backing the stablecoin for the first time in its latest attestation report, which was dated July 16. According to the report, about 61% of its tokens are backed by “cash and cash equivalents,” meaning cash and money market funds.

Yankee Certificates of Deposit – meaning CDs issued by foreign (non-U.S.) banks – comprise a further 13%, U.S. Treasuries account for 12%, commercial paper accounts for 9%, and the remaining tokens are backed by municipal and corporate bonds. 

The company has issued about $22.2 billion worth of USDC, according to the attestation.

It’s unclear what, specifically, Circle has invested in to back USDC. The company intends to go public later this year in a merger with a special purpose acquisition company that would value Circle at $4.5 billion.

According to footnotes in Tuesday’s attestation, the commercial paper has a “minimum S&P rating of S/T A1,” meaning S&P Global Ratings regards the issuer’s ability to meet its financial obligations as being strong.

Circle joins Tether in publishing a rough breakdown of its asset reserves, at least partially answering questions about whether its stablecoin is fully backed. Like Circle, Tether also uses commercial paper to back its USDT token, though commercial paper accounts for far more of Tether’s reserves than Circle’s does.

UPDATE (July 20, 2021, 14:27 UTC): This story has been updated with additional context.