Economic and demographic trends of municipalities in South Africa: an application of Zipf’s rule

English: There are vast differences among South African local municipalities, with a limited number of large municipalities (both in terms of population size and economic activity) and a seemingly disproportionate number of intermediate-sized and small municipalities. No clear systematic national approach has yet been adopted to assess the distribution of core variables at municipal level in South Africa. Zipf’s rule, which postulates a consistent regularity in the size and rank of cities, is applied to disaggregate the performance of South African local municipalities in terms of three variables (population, Gross Value Added and municipal income) within the overall national settlement pattern. The results indicate that the Zipf rank size rule distribution is applicable to municipal level population data in South Africa, but less so for Gross Value Added and municipal income. The position and relative changes of municipalities along the Zipf curve between 2001 and 2011 also provide plausible indications of potential future trajectories of the three variables classified according to the dominant settlement typology within each municipality. The results also emphasise the significant conceptual limitations when using only legally defined administrative municipal boundaries for analysis purposes without also considering economically functional boundaries.