(Bloomberg) -- Pimco saw assets decline 5.4% in the first quarter as the money manager seeks to staunch client redemptions in the wake of co-founder Bill Gross’s abrupt departure.

Assets overseen at the Newport Beach, California-based firm fell to $1.59 trillion at the end of March, from $1.68 trillion at the end of last year and $1.87 trillion at the end of September as Gross left, according to information posted on Pimco’s website.

Its Pimco Total Return Fund, narrowly still the world’s biggest bond mutual fund, has shrunk to $117.4 billion, from $222 billion at the end of August, the month before Gross left, and $293 billion at the peak in April 2013.

The firm suffered the worst year of withdrawals in the history of fund management in 2014 amid its biggest leadership shakeup ever and as performance at some strategies stumbled. Investors pulled $150.2 billion from Pimco’s U.S. mutual funds in 2014, a year during which it lost both of its co-chief investment officers, Gross and Mohamed El-Erian.

Pimco, whose assets declined by about 10% in the fourth quarter, is seeking to reassure investors and stem redemptions. Its Total Return Fund has returned 2.7% this year to beat 94% of peers, according to data compiled by Bloomberg, and withdrawals have slowed in recent months.

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