Some very rough ballpark math:
If the the major oil exporters export around 40 million barrels of oil a day, then every $10 per barrel gap between what the oil exporters spend on imports and what they get on their oil is worth around $150b over the course of the year.
A tiny bit less actually. Call it $145b.
If the oil price stays at $95 a barrel or so over the next year, the oil exporters could spend about $50 a barrel, and still have about $45 a barrel left over to invest in a broad range of assets globally.
If oil exporters are getting $95 a barrel, spending $50 a barrel and saving $45 a barrel, they will have about $650b to invest globally.
That is more than China has to play with. And the fact that China's current account surplus could rise from its 2006 level even with $95 a barrel oil is in some deep sense stunning. The oil exporting economies also have far fewer people than China. Even counting Nigeria.
If the oil exporters attract additional (net) private capital inflows, official asset accumulation in the major oil exporting economies could be even bigger.
And remember, this all assumes that the oil exporters will ramp up spending on imports so that they need $50 a barrel oil to cover their import bill. Not so long ago, any oil exporter that needed $20 a barrel oil to cover its import bill was taking a big risk ...
This analysis draws on my oil and global adjustment paper from this March. Back then I assumed that the oil price would stabilize at say $60 or $70 a barrel, allowing the (rapidly increasingly) imports of the oil exporting economies to cut into the oil exporters' current account surplus.
Suffice to say that oil export revenues are once again rising faster than oil spending and investment.
And that, in turn, makes the question of what the oil exporters are doing will all their petrorevenues all the more pressing.
My guess is that they aren't all being held as petrodollars ....
Update: This New York Times article highlights an important point. It takes less oil to produce a dollar of US GDP now than in the 1970s, but a lot more of that oil is imported now than in the past. The result: more of the windfall from higher oil prices is transferred abroad. The Gulf is now going through its "Texas in the 1970s" period.
Update: Nice graphs from Sudden debt (Hellasious) showing the relative contribution of various regions to overall growth in oil demand. Chinese demand is clearly growing rapidly, but the overall increase in global oil demand isn't coming from China either. The US contribution was significant from 1990-2005, but since 2005 the US has been relatively virtuous ...