Total U.S. retirement assets were $23 trillion as of December 31, 2013, according to data from the Investment Company Institute. This is up 5 percent from $21.9 trillion on September 30, 2013, and up 15.6 percent from year-end 2012.
In addition, retirement savings accounted for 34 percent of all household financial assets in the U.S. at the end of the fourth quarter of 2013.
Assets in individual retirement accounts (IRAs) totaled $6.5 trillion at the end of the fourth quarter of 2013, up from $6.2 trillion at the end of the third quarter. Forty-five percent of IRA assets, or $3 trillion, was invested in mutual funds. Defined contribution plan assets rose 5.1 percent in the fourth quarter to $5.9 trillion, of which $4.2 trillion was held in 401(k) plans. Those figures are up from $5.6 trillion and $4.0 trillion, respectively.
Government pension plans -- including federal, state and local government plans -- held $5.6 trillion in assets as of the end of December, a 5.6 percent increase from the end of September.
Private sector defined benefit plans held $3.0 trillion in assets at the end of the fourth quarter of 2013, and annuity reserves outside of retirement accounts accounted for another $2 trillion.
IRAs held $6.5 trillion in assets at the end of the fourth quarter of 2013, up from $6.2 trillion at the end of the third quarter of 2013. Forty-five percent of IRA assets, or $3.0 trillion, was invested in mutual funds.
The ICI data also found that target-date mutual fund assets totaled $618 billion, showing an increase of 7.9 percent in the fourth quarter. Retirement accounts held the bulk of target-date mutual fund assets, with 90 percent being held through DC plans and IRAs.