A variant of the headline inflation rate was used, because the overall consumer price index is affected directly by changes in the Reserve Bank’s repurchase rate. By including price changes in metropolitan as well as other urban areas, the most comprehensive price index available in South Africa has been targeted.
This challenges the convergence measurement itself because convergence in terms of TFP is not straightforward. Countries belonging to different convergence clubs appear to be experiencing convergence at the level of their club – a concept that is not equivalent to the overall convergence within the EU.