The essence of their argument was that commodity prices had a tendency to decline over the long term. This, until recently, has been largely borne out by empirical evidence. BIS Review 73/2007  1  In the last 140 years there have been 18 commodity cycles, with slumps being more persistent than booms.
In some instances in sub-Saharan Africa, commodity price slumps have lasted over 30 years. However, since 2001, as commodity prices have boomed, we have witnessed impressive economic growth in many of the resource-rich African countries. Notwithstanding the structural shift from a commodity-based country to a more services-oriented one, South Africa has also experienced a concomitant increase in growth over this period. 3.