Estimating and explaining changes in potential growth in South Africa

Estimates of potential output growth in SA have declined from over 3% prior to the Global Financial Crisis (GFC) to just over 2% currently (Ehlers et al, 2013; Anvari et al, 2014; IMF, 2014; SARB MPC statement, March 2015; Kemp, 2015). A similar slowdown has been experienced in several other countries, including most members of the G20 (IMF, 2015). The purpose of this paper is to (i) estimate SA’s level of potential output growth both before and after the GFC using a multi-variate filter technique based on Blagrave et al (2015) and (ii) attempt to explain the apparent decline in the growth potential by investigating the underlying drivers of potential GDP growth using a Cobb-Douglas-type production function (similar to IMF, 2015). It is found that potential growth has declined to around 2.2% post-GFC. It is also determined that the biggest driver of the post-crisis decline in potential growth has been lower productivity growth.

C51, E31, E52

Macroeconomic modelling, Potential output, Multivariate filter, Cobb-Douglas