The latest weekly "Money Market Mutual Fund Assets" report says, "Total money market mutual fund assets decreased by $2.18 billion to $2.796 trillion for the week ended Wednesday, January 12, the Investment Company Institute reported today. Taxable government funds decreased by $7.61 billion, taxable non-government funds increased by $9.25 billion, and tax-exempt funds decreased by $3.82 billion.... Assets of retail money market funds decreased by $6.58 billion to $940.65 billion. Taxable government money market fund assets in the retail category decreased by $1.00 billion to $165.84 billion, taxable non-government money market fund assets decreased by $4.24 billion to $567.55 billion, and tax-exempt fund assets decreased by $1.34 billion to $207.27 billion.... Assets of institutional money market funds increased by $4.39 billion to $1.856 trillion. Among institutional funds, taxable government money market fund assets decreased by $6.62 billion to $650.97 billion, taxable non-government money market fund assets increased by $13.49 billion to $1.081 trillion, and tax-exempt fund assets decreased by $2.47 billion to $123.91 billion."
ICI reports money market fund assets to the Federal Reserve each week. Revisions are due to data adjustments, reclassifications, and changes in the number of funds reporting. Historical weekly money market data back to January 2008 are available on the ICI website.