Norway's $960 billion (£745.6 million) sovereign wealth fund is the world's largest. Here are some facts about the fund:
** The fund invests the Norwegian state's proceeds from oil and gas production for future generations. It was set up as a sovereign wealth fund in 1998. Since then its annual net real return on investment was 3.79 percent, below its 4 percent target.
** The fund has grown so large that it is two-and-a-half times the size of the Norwegian economy. Its size is equivalent to $185,000 for each man, woman and child in Norway.
** It is managed by a unit of the central bank, called Norges Bank Investment Management (NBIM). It answers to the board of the central bank and the Norwegian parliament.
** It can invest in stocks, bonds and real estate abroad only. It owns on average 1.3 percent of global equities.
** To prevent the economy from overheating, Norwegian governments can only use a limited amount of the overall value of the fund.
** Until recently the so-called fiscal spending rule ("handlingsreglen") was for an average of 4 percent of the fund's value to be used for national budgets. It is now 3 percent, partly because the fund has grown so large but also out of concern that the future return on investment could become smaller.
** It also has an ethical mandate. It does not invest in companies that produce tobacco, nuclear weapons or anti-personnel landmines, among other criteria. So far some 66 companies have been excluded on ethical grounds.
** The fund's biggest country holding at end-2016 was the United States (37.2 percent of the fund's value), followed by Britain (9.1 percent) and Japan (8.3 percent).
** Its three biggest equity holdings were Apple (AAPL.O), Nestle (NESN.S) and Royal Dutch Shell (RDSa.L) as of March 31.
** Its three biggest government bond holdings as of March 31 were U.S. Treasuries ($67 billion), Japanese government bonds ($22 billion) and German government bonds ($13 billion).
Sources: NBIM, Norges Bank, Statistics Norway
(Reporting by Gwladys Fouche; Editing by Dale Hudson)