As major economies across the globe—including the U.S.—followed QE measures in the aftermaths of the 2008 financial crisis, a good portion of the QE money made its way into money market mutual funds as a haven. This migration of funds has led to interest rates remaining low for a long duration, and the diminishing of returns from money market funds.
footnote*For the 10-year period ended June 30, 2019, 9 of 9 Vanguard money market funds outperformed their Lipper peer-group averages. Results will vary for other time periods. Only mutual funds and ETFs (exchange-traded funds) with a minimum 10-year history were included in the comparison. Source: Lipper, a Thomson Reuters Company. The competitive performance data shown represent past performance, which is not a guarantee of future results. View fund performance
Government Normally at least 99.5% of the fund’s total assets are invested in cash, U.S. government securities and/or repurchase agreements that are collateralized fully (i.e., collateralized by cash or government securities)—including at least 80% in U.S. government securities and repurchase agreements for those securities. Certain issuers of U.S. government securities (e.g., “Government-Sponsored Enterprises” such as Fannie Mae, Freddie Mac, and the Federal Home Loan Banks) are sponsored or chartered by Congress, but their securities are neither issued by nor guaranteed by the U.S. Treasury.
Looking closer we see that if you can meet the $3,000 minimum investment size, Vanguard’s VMMXX offers an appealing combination of relatively high returns with low expenses. If you don’t have a large amount of cash to invest, you should note that both FMPXX and FIDXX have $1MM investment minimums. If you have less than $1,000, SPRXX doesn’t meet the yield and expense ratio thresholds we laid out, but it doesn’t have an investment minimum.