Hmmm, the maths seems a bit off. Looking at the international average salary of $19,188, that would be approximately R230,000 so therefore the percentage difference in comparison to the world average should be lower, not higher than the comparison against local currency.
With the figures the way they are, it would require an exchange rate of R5.50/$. I know we get paid fairly well in world terms, but I know we are nowhere near Australia at the moment. Maybe this would explain it.
It is using International Dollars, with one International Dollar set to one US Dollar. This is used so that PPP is taken into account