The departure comes just one week after the fund appointed a new chief executive. : The Guardians of NZ Superannuation Fund has confirmed the chief investment officer is departing just one week after it announced the appointment of a new chief executive. Chief investment officer Stephen Gilmore will leave the NZ Super Fund at the end of June 2024 to take up the role of chief investment officer at CalPERS, the largest pension plan in the United States with US$494 billion under management.