The savings glut in some countries is, of course, a reflection of the current account surpluses accumulated by Asian and oil exporting countries.

And the low ratios are the counterpart of the current account deficits in countries like South Africa, which has a deficit of 6.5 percent of GDP.

The savings glut in countries with large surpluses has financed the deficits in other countries, allowing growth to continue around the world.

But this may not continue.

The IMF warns that the pattern of savings is likely to shift over time.

Surpluses of oil exporting countries will start to decline as spending starts to match their earnings potential.

And the IMF says savings in China will decline as precautionary savings are reduced, consumption rises "substantially" and the Chinese start using credit.

This all means higher global interest rates and slower growth are on the way, according to the IMF.

Financing will become less readily available, which will create a problem for the US, South Africa and other countries with deficits.

So what will we do?

The IMF unfortunately doesn't provide any answers. But Reserve Bank governor Tito Mboweni may well think higher interest rates rates will do the trick.

The upside from South Africa's point of view is that the local savings ratio improved quite dramatically this year.

It rose to 14.8 percent in the first quarter and 15.9 percent in the second. The latter increase is the highest since the third quarter of 2003, when it made 16.8 percent.

This may be due to the higher level of interest rates this year, which makes savings a more attractive proposition.

But despite IMF fears about falling savings levels, interest rates around the world are either levelling out or are starting to fall, according to Moody's economists Ruth Stroppiana and Melanie Averall.

They say most developed economies have reached the end of the rate-raising cycle, while emerging economies are starting to cut.

The Turkish central bank last week "opted to cut more aggressively than anticipated, slashing interest rates by half a percentage point", they say. "A number of Asian and Latin American emerging economies are also cutting rates".

And they expect Hungary to follow suit.

That makes the chances of another local interest rate hike less likely - whatever Mboweni thinks of the savings rate.