Bitwise Asset Management says a new cryptocurrency index fund keying in on decentralized finance, or DeFi, has become its fastest growing investment product. 

Bitwise's DeFi Crypto Index fund has brought in at least $32.5 million from accredited  investors since it started accepting outside capital in February, according to a March 2 U.S. regulatory filing.

Bitwise chief investment officer Matt Hougan said the rate of investment in the DeFi fund is showing "no signs of slowing," CoinDesk reported

Decentralized finance has exploded in the last year. Funds locked in on DeFi protocols went from $1 billion a year ago to about $40 billion today, according to data provider DeFi Pulse

Decentralized finance protocols allow users to borrow, lend and generate yield from their crypto assets. Users can also trade in a decentralized way, depositing their assets into pools that exist on blockchains and then buying or selling against them. Proponents say DeFi cuts out intermediaries endemic to traditional markets. 

The protocols with the most assets locked are Maker, Compound and Aave, with about $15 billion collectively. They are all built on the Ethereum blockchain, with DeFi Crypto Index Fund maintaining exposure to all three digital assets. 

DeFi has begun to attract the attention of other asset managers. London-based CoinShares has worked with a DeFi community called Index Coop to issue an Ethereum token that mimics its gold and cryptocurrencies product. 

Bitwise is also working to expand access to its funds. It has filed with regulators to allow its bitcoin fund to be traded over-the-counter.