Assets in separately managed accounts rose 25% in the first quarter from the year-ago period, to $736.4 billion, up from $590.1 billion, according to data from the Money Management Institute. From the previous quarter, SMA assets grew 8.6%, from $678.1 billion at the end of last year.

The average account size is now $322,422, up nearly 13% from $285,909 a year ago, while the total number of SMA accounts is now 2.27 million, up 9.1% from a year ago.

"Assets continue to grow because increasing numbers of investors, particularly those contemplating retirement over the next 15 years, are seeking professional investment advice to construct an individualized investment solution using various investment managers with various investment vehicles," explained Mark Pennington, a partner with Lord Abbett.

"When an advisor seeks to create a customized investment solution, a managed account is often a key element of the plan," he continued.

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