U.S. spot Bitcoin ( BTC ) investment products had another record weekly inflow, with $2.9 billion in new assets added.

According to a March 18 report by digital asset investment company CoinShares, year-to-date, a total of $13.2 billion in new capital has flowed into investment products such as spot Bitcoin ETFs, with $74.61 billion worth of Bitcoin now under custody. Bitcoin products accounted for 97% of the total inflows. "Digital asset investment products saw record weekly inflows totaling US$2.9bn, beating the prior week's all-time record of US$2.7bn," wrote CoinShares analyst James Butterfill. 

Bitcoin investment products see another record $2.9B inflow image 0 Weekly Crypto Asset inflows as of March 15 (CoinShares, Bloomberg)

Interestingly, Ether ( ETH ) and other altcoin investment products have not been as popular with investors, with their year-to-date inflows combined amounting to a tiny fraction of the total that has gone into Bitcoin. Furthermore, despite an all-time high ETF inflow, the price of Bitcoin has tumbled by 7% in the past week and now trades at $67,418 at the time of publication.

Outside of the U.S., crypto exchange products have seen record outflows, with investors pulling $738 million from Bitcoin exchange-traded products on German, Canadian, and Swedish exchanges and, in part, switching them for their U.S. counterparts. Compared to management fees of upwards of 1% per annum, U.S. Bitcoin ETFs charge as little as 0%  on a portion of their inflows. Since their approval by the Securities and Exchange Commission in January, U.S. Bitcoin ETFs have captured more than 80% of the spot Bitcoin ETF market share. 

The popularity of Bitcoin ETFs has led regulators such as the U.K.'s Financial Conduct Authority (FCA) and Hong Kong's Securities Futures Commission (SFC) to soften their stance on such products. On March 11, the FCA said it would "not object to requests from Recognised Investment Exchanges (RIEs) to create a U.K. listed market segment for cryptoasset-backed Exchange Traded Notes." Similarly, Hong Kong's SFC receives its first spot Bitcoin ETF application on January 29 . 

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