That desire for customization has also translated to 401(k) retirement plans that increasingly have auto-enrollment features for employees and target-date funds that provide a simple asset-allocation model for individuals based on their age and risk tolerance.
As investors age, the portfolio will progressively tilt more toward conservative fixed-income investments.
"Some people have unique demands, but the trend we see is that one size fits most," said Young, whose firm performs record-keeping for about 20 percent of 401(k) assets in the country. "Target-date funds and managed accounts are accounting for the bulk of the growth in the industry now."
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How individual investors get their financial advice is likely to have a major impact on their demand for investment products going forward.
Registered investment advisors, for example, have become enthusiastic users of ETFs in constructing diversified portfolios for their clients. As the fastest-growing distribution channel in the advisory industry, RIAs have helped fuel growth at the major ETF managers Vanguard, BlackRock and State Street Advisors.
In contrast, higher-cost, actively managed mutual funds sold through the large Wall Street wire houses and independent brokers have experienced much less growth.