Norway's massive sovereign wealth fund posted a 2.7 percent return on investments in 2015, the lowest return since 2011.

The Norwegian central bank, which manages the fund, said Wednesday that last year "was a volatile year, with negative interest rates, currency turmoil, falling oil prices and weaker growth expectations for emerging markets."

The fund's market value rose to 7.48 trillion kroner ($854 billion) on Dec. 31, 2015, from 6.43 trillion kroner a year earlier.

Norway invests income from its offshore oil and gas sector in the fund, which is officially called The Government Pension Fund Global.