The top five target-date managers accounted for $1.2 trillion of the total of $1.53 trillion as of June 30 and held the same spots they've held since the 2015 survey. Vanguard led the way again, reporting $469.6 billion in proprietary assets, up 23.9% from a year earlier; Fidelity with $211.1 billion, up 12%; T. Rowe Price Group Inc., $205.3 billion, up 18.3%; BlackRock Inc., $203.2 billion, up 21.5%; and J.P. Morgan Asset Management, $114.2 billion, up 13%. (Mutual funds, commingled trusts and separate accounts are included under the target-date total.)
David Blanchett, head of retirement research, Morningstar Investment Management, Chicago, said in a telephone interview that Vanguard's faster pace of growth is not surprising.
"I really think Vanguard's asset share will continue to maintain. I wouldn't be surprised to see ... Fidelity's and the T. Rowe Price's decline because they're not as popular on non-Fidelity and non-T. Rowe Price platforms," Mr. Blanchett said.
Vanguard Group has been the beneficiary of automated features as it has supplanted Fidelity Investments atop of the list of mutual funds used by DC plans.
"The thing that continues to be similar as prior years (is) ... the power of default and the growing amount of automation," said Scott Conking, principal and head of institutional investor services at Vanguard Group, in a telephone interview.
"I think generally," Mr. Conking said, "we are really pleased with the direction the defined contribution environment is going because one of the things that is really important to us is that participants get in the plan, they save, and they invest, diversified, for a long period of time. The trends are very,very positive."
Capital Group, which offers the American Funds family, ranked sixth and reported by far the largest growth in target-date funds for the year ended June 30 —a 47.7% jump from the previous year to $86.7 billion in proprietary target-date assets.
Sue Walton, Chicago-based senior defined contribution strategist at American Funds, said in a telephone interview that the success of the company's single target-date fund series comes down to an emphasis on creating "the best outcomes for the strategies."
"It's an eye toward keeping participants in plans, making sure those strategies work beyond that target date, 20 to 30 years into retirement," Ms. Walton said, noting that the series' glidepath is managed 30 years into retirement.
"It's managing for that longevity risk," Ms. Walton said. "People are living longer, health-care costs are on the rise. Adding that additional 50 basis points or that 1% over the long term is going to have a meaningful impact."