Empirical analysis of the effect of exchange rate volatility on share returns: Evidence from mining companies listed on the Johannesburg Stock Exchange, South Africa

Abstract

Type of the article: Research ArticleAbstractExchange rate volatility is a critical macroeconomic risk factor in emerging markets, particularly for export-oriented sectors such as mining in South Africa. The South African mining sector is inherently affected by exchange rate volatility, yet it is the economy’s largest foreign-currency earner through the export of mining resources. The study examines the effect of exchange rate volatility on mining companies’ share returns within South Africa. The study applies the system Generalized Method of Moments (GMM) estimator to account for both endogeneity and dynamic effects, using panel data from 15 Johannesburg Stock Exchange-listed mining companies over the period 2011 to 2024. The empirical results reveal that exchange rate volatility has a positive and significant effect on the share returns of mining companies, with a coefficient of 0.808, and on total returns (1.094). This indicates that higher currency risk is related to higher return premiums. In contrast, a negative and significant relationship exists between exchange rate volatility and share prices (99.45), implying an adverse valuation effect during heightened uncertainty. Regarding the control variables, GDP growth has a positive effect on share returns (8.978), while oil prices exhibit a negative relationship (–0.327). The results of the study support the risk-return trade-off and the flow-oriented exchange rate approach. The study therefore shows that exchange rate volatility plays a dual role through the enhancement of returns while depressing valuations. This highlights the benefits of implementing currency risk management strategies for investors and policymakers.