This paper examines the Purchasing Power Parity (PPP) hypothesis in a number of Sub-Saharan countries by testing the order of integration in the log of their real exchange rates vis-à-vis the US dollar. I(d) estimation techniques based on both asymptotic and finite sample results are used. The test results led to the rejection of PPP in all cases: orders of integration below 1 are found in fourteen countries, but the unit root null cannot be rejected.

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