Vanguard investor homepage on a phone screen (Photo: Shutterstock)

Vanguard has admitted it provided investors in several money market funds inaccurate information about the estimated income they could expect to earn.

The error on client statements continued for almost a year, according to Dan Wiener, editor of The Independent Adviser for Vanguard Investors, who first reported the problem.

In response, Vanguard issued a statement that it “recently corrected an issue on certain client statements where money market funds were displaying inaccurate estimated yields and annual income” and notified clients of the correction on their monthly statements. It noted “there was no impact to clients’ fund holdings, distributions, or account balances.”

The error occurred on statements for as many as nine money market funds, including federal government, Treasury and some muni money market funds. Vanguard is liquidating two of the funds this month: the Pennsylvania Municipal Money Market Fund and the Vanguard New Jersey Municipal Money Market Fund. Notification of the error is included in the footnote of clients’ October statements, according to Wiener.

(Related: Vanguard to Liquidate 2 Money Market Funds)

He attributed the error to a computer glitch, which is nothing new for Vanguard nor for many other asset managers. In Monday’s frenetic rally on Wall Street, customers of Vanguard, Fidelity, Merrill Lynch, Charles Schwab and TD Ameritrade reported issues logging into their accounts.

(Related: Trading Outages at Schwab, E-Trade, TD Ameritrade, Other Platforms Irk Investors)

Vanguard’s computer problems are “a sign of too much growth too fast without having the systems in place to keep up with it,” Weiner said. “They’re in the big leagues now and need to have systems that reflect that.”

Morningstar strategist Alec Lucas cautioned that investors should not overreact to Vanguard’s money market reporting problem because the mistake did not affect what investors earned but rather what they were projected to earn in an asset class that is not expected to generate big returns.

But he noted that there have been questions on whether Vanguard has invested enough in technology and customer services because of its “lean cost structure,” which also benefits investors indirectly: Under its ownership structure, Vanguard fund investors own Vanguard funds and therefore Vanguard.

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