Money fund assets plunged in the latest week, after dipping last week and rising for the 7 weeks prior. The latest "Money Market Fund Assets" report says, "Total money market fund assets decreased by $20.75 billion to $2.71 trillion for the week ended Wednesday, December 21, the Investment Company Institute reported today. Among taxable money market funds, government funds decreased by $21.12 billion and prime funds decreased by $210 million. Tax-exempt money market funds increased by $580 million." It continues, "Assets of retail money market funds increased by $2.83 billion to $982.39 billion. Among retail funds, government money market fund assets increased by $3.25 billion to $604.03 billion, prime money market fund assets decreased by $850 million to $251.74 billion, and tax-exempt fund assets increased by $440 million to $126.61 billion.... Assets of institutional money market funds decreased by $23.58 billion to $1.73 trillion. Among institutional funds, government money market fund assets decreased by $24.37 billion to $1.60 trillion, prime money market fund assets increased by $640 million to $123.13 billion, and tax-exempt fund assets increased by $150 million to $4.73 billion." Total money fund assets are down year-to-date by $47.0 billion, or 1.7%. Yields on money market funds rose in the latest week, according to Crane Data's Money Fund Intelligence Daily. Our Crane 100 Money Fund Index rose by 9 basis points to 0.42%, and our broader Crane Money Fund Average rose by 6 basis points to 0.24% (7-day net simple yields). Prime Institutional MMF yields rose by 10 bps to 0.46%, while Govt Inst MMF yields rose by 8 bps to 0.26% and Treas Inst MMF yields rose by 6 bps to 0.22%. Thus, spreads between Prime Inst money funds and Treasury Inst funds have grown to 24 basis points and spreads between Prime and Govt Inst MMFs have grown to 20 bps.