The U.S. retirement market was valued at $27.2 trillion at the end of the third quarter this year, according to the Investment Company Institute.

That marked a full $1 trillion gain from the end of the second quarter in 2017, and nearly $10 trillion more than at the end of 2010.

Government and private sector-sponsored defined benefit plans, defined contribution plans, IRAs, and annuity reserves are counted by the ICI. Social Security benefits are not.

IRAs held $8.6 trillion at the end of the third quarter, representing the largest swath of the retirement market, an increase of 2.7% from the end of the second quarter, and up from $5 trillion in 2010.

About half of IRA assets are held in mutual funds, with $2.3 trillion being managed in equity funds.

Defined contribution plans held 7.7 trillion, up 2.5% from the second quarter, for an increase of nearly $3 trillion since 2010. 401(k) plans held $5.3 trillion.

Mutual funds accounted for $3.5 trillion, or 65% of the assets in 401(k) plans, with $2.1 trillion held in equity funds.

Strong equity markets have continued to stretch total retirement savings assets into new record territory. The Dow Jones Stock Exchange is up more than 25% in 2017.

Target-date funds reached $1.1 trillion in assets by the end of the third quarter, up 5% from the previous quarter.

About 67% of TDF assets are held in defined contribution plans, and another 20% held in IRAs.

The $708 billion in TDFs held in DC plans represents perhaps the most stratospheric assent for any investment vehicle in retirement plans. In 2010, TDFs in DC plans held just $240 billion.

Private sector defined benefit plans held $3.1 trillion at the end of third quarter.

In 2000, private sector defined benefits accounted for 17% of what was then an $11.6 trillion retirement market.

Today, the plans account for about 11% of total retirement assets.

As a percentage of total assets, defined contribution plans have increased marginally over the past two decades.

In 2000, DC plans accounted for 26% of what was then an $11.6 trillion retirement market.

Today DC plans account for 28% of the $27.2 trillion retirement market.

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