A release from the Investment Company Institute tells us that, "Retirement Assets Total $34.9 Trillion in Fourth Quarter 2020." It includes data tables showing that money market funds held in retirement accounts jumped to $574 billion in total, or 13% of the total $4.333 trillion in money funds. MMFs represent 5.2% of the total $11.118 trillion of mutual funds in retirement accounts. The release says, "Total US retirement assets were $34.9 trillion as of December 31, 2020, up 7.5 percent from September and up 9.3 percent for the year. Retirement assets accounted for 33 percent of all household financial assets in the United States at the end of December 2020. Assets in individual retirement accounts (IRAs) totaled $12.2 trillion at the end of the fourth quarter of 2020, an increase of 9.1 percent from the end of the third quarter 2020. Defined contribution (DC) plan assets were $9.6 trillion at the end of the fourth quarter, up 6.8 percent from September 30, 2020. Government defined benefit (DB) plans—including federal, state, and local government plans—held $7.1 trillion in assets as of the end of December 2020, a 7.6 percent increase from the end of September 2020. Private-sector DB plans held $3.4 trillion in assets at the end of the fourth quarter of 2020, and annuity reserves outside of retirement accounts accounted for another $2.5 trillion." The ICI tables also show money funds accounting for $391 billion, or 7%, of the $5.454 trillion in IRA mutual fund assets and $282 billion, or 3%, of the $5.665 trillion in defined contribution plan holdings.