US bitcoin exchange-traded funds (ETFs) have posted their longest run of daily net outflows since listing at the start of the year, part of a wider retreat from riskier assets in a challenging period for global markets.

Investors pulled close to US$1.20 billion in total from the group of 12 ETFs over the eight days through Sept 6, data compiled by Bloomberg showed. The drop comes amid a rocky period for shares and commodities on economic growth worries.

Mixed US jobs data and deflationary pressure in China are both taking a toll on traders. The uncertainty is buffeting the cryptocurrency market, whose gyrations have become more closely tied to moves in stocks based on a rising short-term correlation between the two.

Bitcoin has struggled in September, posting a loss of approximately 7%. But the largest digital asset eked out modest gains over the weekend and climbed roughly 1% to US$54,870 as of 1pm on Monday in Singapore.

“The small relief rally seems to be driven in part by some prominent influencers closing out their shorts,” said Sean McNulty, the director of trading at liquidity provider Arbelos Markets. He cited as an example a recent social media post from Arthur Hayes, a co-founder of the BitMEX trading platform.

An improved showing by Donald Trump, the pro-crypto Republican nominee for the US presidential election, in polls and prediction markets may also be playing a role, McNulty said. He reported greater demand for options hedges in case Tuesday’s debate between Trump and Democratic nominee Vice President Kamala Harris stirs volatility. Harris has yet to detail her stance on crypto.

The US bitcoin ETFs investing directly in the original cryptocurrency debuted in January with much fanfare. Unexpectedly strong demand for the funds helped to drive the token to a record high of US$73,798 in March. The inflows subsequently moderated and bitcoin’s year-to-date rally has cooled to about 30%.

The token will likely trade in its recent US$53,000 to US$57,000 range until the US releases consumer-price data on Wednesday, said Caroline Mauron, a co-founder of Orbit Markets, a provider of liquidity for trading of digital-asset derivatives. The inflation numbers may shape expectations for the pace of anticipated monetary easing by the Federal Reserve in the US.

  - Bloomberg