Surging investor appetite for pot stocks has led one cannabis-focused exchange-traded fund (ETF) to break the billion-dollar mark for the first time.

In a press release, The Horizons Marijuana Life Sciences Index ETF (HMMJ), which offers direct exposure to North American-listed companies with business activities in the marijuana industry, said its total assets under management have grown to more than $1 billion Canadian dollars —  $760 million U.S. dollars at the current exchange rate. The ETF’s shares have surged 43% in the past month, according to CNBC, and 124% since it debuted on the Toronto Stock Exchange in April 2017 as investor enthusiasm for its top holdings continues to soar.

Pot stocks have rallied in anticipation of Canada’s upcoming recreational marijuana legalization and speculation that more liquor producers are keen to partner up with the industry after Corona beer maker Constellation Brands Inc. (STZ) announced a $4 billion investment in marijuana company Canopy Growth Corp. (CGC). Canopy, HMMJ’s largest holding according to S&P Capital IQ, has seen its stock price more than double since the deal was announced. Its other holdings include Aurora Cannabis Inc. (ACB), Aphria Inc. (APH), GW Pharmaceuticals Plc. (GWPH) and Cronos Group Inc. (CRON).

“One of the key drivers of HMMJ’s rapid asset growth speaks to the investor demand and desire for a diversified portfolio of cannabis companies versus buying individual stocks," Horizons CEO Steve Hawkins said in a statement. “While there are clearly leaders in the marijuana equity sector, nobody knows for sure which companies will truly be successful over the long term or even be swallowed-up.”

HMMJ, which holds 40 stocks mainly focused on medical marijuana, reached the $1 billion Canadian dollar milestone despite experiencing fluctuating demand last month as some investing experts questioned the valuations of some of the sector’s biggest names.

According to Bloomberg, investors pulled a total of $15.9 million Canadian dollars out of the fund in six of the seven trading days between Aug. 21 and Aug. 29, before plowing $14.1 million Canadian dollars back into the ETF on Aug. 30. A strong end to the month brought total inflows in August to $12 million Canadian dollars. (See also: Marijuana Stocks: Citron Fails to Kill Buzz.)

The best-performing cannabis-focused ETF in August was the U.S.-listed ETFMG Alternative Harvest (MJ) ETF. According to CNBC, MJ is now nearing $500 million in assets after attracting inflows of more than $30 million in August. (See also: Marijuana ETF Attracts $22 Million in August.)