Since the Pension Protection Act of 2006 was signed into law, the growth of target-date funds has been staggering. But that has led to lagging modernization in the funds’ asset mix of stocks, bonds, cash equivalents and other investments — particularly the “other” category, which increasingly includes real estate.

At the end of June 2014, approximately $678 billion was invested in target-date mutual funds, reports Washington, D.C.–based Investment Company Institute. More important, adds the institute, net cash flows into target-date funds have grown significantly; target-date mutual funds received $53 billion in net new cash flow during 2013, compared with $22 billion in 2005 and $4 billion in 2002.

In addition, Boston-based Cerulli Associates reports target-date funds will continue to grab a greater share of 401(k) assets, capturing 88 percent of new contributions to the plans and representing 35 percent of total 401(k) assets by the end of 2019.

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