OSLO, Feb. 27 (Xinhua) -- Norway's oil fund had a return of 13.7 percent last year, which is more than 1,000 billion kroner (127.3 billion U.S. dollars), online newspaper E24 published Tuesday.

This is the sixth year in a row that the fund delivers positive return. The fund is formally known as the Government Pension Fund Global (GPFG) and ranked as the world's biggest sovereign wealth fund.

The reason for this was especially solid return on equities, Norges Bank Investment Management (NBIM), which manages the fund, said in a report.

The total value of the fund rose by 978 billion kroner from 2016 to 8,488 billion kroner at the end of 2017. Norwegian kroner depreciated against several currencies throughout the year, which raised the fund's value by 15 billion kroner, NBIM wrote in the report.

"The fund's total return since its start has exceeded 4,000 billion kroner. A quarter of this return was earned in 2017, after a very good year for the fund," NBIM's director Yngve Slyngstad was quoted as saying.

Equity investments made the most of a return of almost 20 percent, he added.

"The Board of Directors is satisfied that the return in both 2017 and over time has been good and higher than the return on the fund's benchmark index," said Oystein Olsen, head of Norges Bank, central bank of Norway, who also holds the position of chairman of the board of the oil fund.

By the end of 2017, 66.6 percent of the fund was invested in equities, 30.8 percent in bonds, and 2.6 percent in non-listed property.

The oil fund itself is in phase of some possible important changes. The central bank would like the fund to dispose of its oil shares in order to reduce Norway's overall risk associated with sudden fluctuations in oil prices.

They also wish that the fund owns bonds in fewer currencies than today, especially suggesting bonds issued in dollars, euros and pounds. This could make extensive sales in, among other things, Japanese and Mexican bonds.

The Norwegian government has taken into consideration that the fund's return is expected to fall over the next few years. This led to decision to limit the use of oil money from four to three percent of the fund's annual value, E24 wrote.