Consider, if you will, an oil exporting nation. Consider further those nations whose commodity exports far exceed their budgetary needs. What is a nation to do with such excess wealth?
There are two main approaches to this. The first is the more conventional strategy inherited from central banks, in many ways the precursors to SWFs. This method, which I will call risk-off, seeks simply to hold foreign exchange reserves, usually the US dollar, in the form of high quality, low risk assets, usually US Treasury bonds.
The second strategy, which I will call the risk-on, borrows heavily from pension and endowment funds. Investments are made not to protect value, but to create value so as to meet future obligations. Not only is public equity as an asset class targeted, but all manner of alternative investments including but not restricted to private equity, hedge funds, real estate and high yield debt.
So as not to confuse the point that I am trying to make, I would like to clarify that there is no right or wrong to which method a government chooses, as the choice is driven by policy considerations not investment considerations.
Back to our story. If an oil exporting country with a risk-on strategy suddenly faced oil prices dropping by 50%, what is the net effect to its revenue? Using Norway as an example, their circa 1.7 million barrels per day of export would lose USD 85 million per day in revenue or USD 31 billion per year.