The average daily trading volume (ADV) of bitcoin futures contracts on the Chicago Mercantile Exchange (CME) went up by 41% in the third quarter of this year, according to data from the exchange itself.

The data, published via Twitter, shows over 5,000 contacts (25,000 BTC) were traded, while adding that open interest (OI) – the amount of open contracts – has risen by 19% this quarter as the number of open contracts is of 2,870.

Although CME’s tweet shows bitcoin futures contracts trading volume has been growing, its growing at a slower pace than in the last quarter. Back in July, the exchange revealed Q2 saw an increase of 93% in average daily trading volume, and of 58% in OI.

The CME Group is notably one of the largest exchanges in the world. It launched bitcoin futures contracts late last year, on December 17, when most cryptocurrencies were close to their all-time highs and shortly after the Chicago Board Options Exchange (CBOE) launched BTC futures.

Cryptocurrency futures have become somewhat controversial, as a report published by the Wall Street Journal claimed a dispute between CME and four cryptocurrency exchange prompted the Commodities Futures Trading Commission (CTC) to probe crypto markets for potential manipulation.

Bitcoin bull Tom Lee, the founder of Fundstrat Global Advisors, has also argued that bitcoin futures contracts were to blame for the crypto market’s “gut-wrenching” drop, as he noticed “dramatic price changes around CBOE futures expirations.” The drop, which led to a months-long bear market, saw BTC futures volumes temporarily plummet.

Some speculate ether (ETH) futures may soon be coming to the CME and to the CBOE Futures Exchange (CFE), as the US Securities and Exchange Commission (SEC) declared the cryptocurrency isn’t seen as a security. While they may be coming, the popular exchange’s CEO, Terry Duffy, claimed it won’t add new crypto futures anytime soon.

Elsewhere, ether futures already exist as UK-based exchange Crypto Facilities launched the product this year. Coinfloor, another UK-based platform, launched physically settled bitcoin futures contracts in March of this year.