U.S. money market fund assets have reached a record $7.2 trillion, reflecting a substantial increase over the past two years. Retail investors alone have parked more than $2.1 trillion in these funds, marking an all-time high. This surge in money market holdings represents a rapid accumulation of cash compared to historical trends, as it took two decades from 1981 to 2001 for money market funds to grow by $2 trillion, whereas the same growth occurred within just two years recently. Despite the large absolute amount, money market assets constitute only about 14% of the S&P 500 market capitalization, a relatively low proportion historically. Analysts note that much of this cash is likely to remain on the sidelines rather than flow into equities. Additionally, money market assets as a percentage of total assets have been rising for nearly a year, currently standing at 18%, which is not high compared to historical levels.