Fitch Ratings' "U.S. Money Market Funds: July 2021" tells us, "Total taxable money market fund (MMF) assets decreased by $76 billion from May 28, 2021 to June 30, 2021, according to iMoneyNet data. Government MMFs lost $67 billion in assets during this period, and prime MMF assets decreased by$9 billion.... MMFs have been reducing exposure to treasury while increasing exposure to repo. Treasury holdings decreased by $134 billion, while repo increased by $251 billion from May 31 to June 30, 2021, according to Crane Data. Of this amount, $839 billion, or 50% of all repo, has been invested in the reverse repo program (RRP) managed by the Federal Reserve Bank of New York (Fed), which has been growing over the past few months." It adds, "As of June 30, 2021, institutional government and prime MMFs net yields were 0.02% and 0.03% per iMoneyNet data, respectively, unchanged from end of May. MMF managers have been waiving fees to encourage investment in the funds during this low interest rate environment."