Spot bitcoin exchange-traded funds in the U.S. logged their 13th consecutive day of net inflows on Thursday, drawing in $48.71 million. Major movements of funds were spotted in two bitcoin funds from Fidelity and from Ark Invest and 21Shares yesterday. 

Fidelity’s FBTC led net inflows worth $119 million, while Ark’s ARKB saw nearly $100 million in net outflows, according to data from SoSoValue. ARKB’s Thursday outflow marked its largest since its debut in January.

BlackRock’s IBIT, the largest spot bitcoin fund by net assets, logged net inflows of $2 million. Grayscale’s GBTC, which recently became the second largest, saw zero flows. Bitwise’s BITB added $26 million worth of funds, while Invesco and Galaxy Digital’s bitcoin ETF reported $2 million in net inflows.

“The unusual spot bitcoin ETF flows appear to be influenced by investor uncertainty regarding the Federal Reserve's interest rate path, particularly in anticipation of major economic reports due out from the U.S. on May 31,” BTC Markets’ Crypto Analyst Rachael Lucas told The Block.

“If U.S. inflation numbers exceed expectations and personal income and spending trends rise, it could dampen investor optimism about a potential Fed rate cut in September. A more hawkish Fed could negatively impact demand for riskier assets, including bitcoin and related ETFs,” Lucas said.

In the past 13 days, the U.S. spot bitcoin ETFs saw total net inflows of over $2 billion. The funds are in their second-longest positive streak since their listing, only behind the 17 straight days of net inflows that started in January. 

However, the total volume of flows in the U.S. spot bitcoin ETFs remained significantly smaller than their peak in March, The Block’s data dashboard showed.

Meanwhile, Grayscale filed its amended S-1 registration statement for its spot Ethereum fund on Thursday, a day after BlackRock’s filing. More S-1 filings are expected to arrive as the SEC has asked issuers to submit their forms by Friday.