上百只货币基金，七日年化收益率跌破1%

Core Viewpoint - The yield of money market funds has been declining throughout the year, with a median annualized yield of 1.24% as of December 16, 2023, leading to many funds implementing purchase restrictions to protect long-term investors from dilution of returns due to arbitrage activities [1][2][4]. Group 1: Yield Trends - As of December 16, 2023, 941 money market funds reported a median seven-day annualized yield of 1.24%, with 102 funds yielding below 1% and over 300 funds yielding between 1% and 1.2% [2]. - The largest fund, Tianhong Yu'ebao, maintained a yield above 1%, specifically at 1.014%, showing a slight recovery from a previous low of 1.001% [2]. Group 2: Fund Management Responses - In response to declining yields and arbitrage pressures, several fund companies have announced purchase restrictions or even halted new subscriptions to protect existing investors [5][6]. - Specific funds, such as the Fuan Da Cash Fund, have implemented measures to suspend subscriptions while allowing transactions through certain channels to maintain operational stability [5]. Group 3: Market Dynamics - The increase in money market fund sizes, which grew by over 380 billion units to 15.05 trillion units by the end of October, contrasts with the declining yields, influenced by lower interest rates on demand deposits and market volatility [3]. - The phenomenon of "deposit migration" has affected banks' liquidity management, increasing friction in fund flows and contributing to yield volatility in the money market [2]. Group 4: Arbitrage Concerns - Fund companies are limiting purchases to prevent arbitrage activities that dilute returns for existing investors, as new investors can benefit from yield accrual during the time funds are held in transit [6][7]. - Regulatory measures have been introduced to tighten the timing of fund subscription settlements, yet loopholes remain, prompting fund companies to adopt purchase limits as a protective strategy [7].