The Government Pension Investment Fund is likely to record losses of more than ¥5 trillion for fiscal 2015, which ended Thursday, amid a deteriorating investment environment since January, according to recent estimates by financial experts.

The GPIF, one of the world's largest institutional investors, decided on a major shift in investment policy in October 2014 at the urging of Prime Minister Shinzo Abe's administration, placing more emphasis on riskier assets such as stocks while cutting holdings of Japanese government bonds.

The fund, which manages employee and national pension funds overseen by the Health, Labor and Welfare Ministry, reported last month ¥2.31 trillion of gains for the 2015 calendar year.