The interaction between oil price shocks, currency volatility and stock market prices: evidence from South Africa

Crude oil is an essential and strategic commodity in modern economies. Therefore, energy price fluctuations have the potential of affecting the economic welfare of a country. For instance, they have the potential to undermine the government’s attainment of its economic growth targets (National Treasury, 2016:2). The South African Reserve Bank (SARB) also considers oil price movements to be one of the major threats to currency volatility and the continued attainment of its inflation targets of about (3-6, per cent), as evidenced by numerous recent statements by its monetary policy committee (SARB, 2016:5-13). This study used co-integration tests to investigate the interaction between oil price shocks, exchange rates and stock market prices in South Africa over the period 1 January 2011 to 1 April 2018. The study employed the Johansen co-integration test. The results found no long run co-integration between oil prices, exchange rate and stock market prices. Therefore, this study adopted the VAR model for causality tests. Using the VAR model, this study found the existence of a unidirectional causality between stock prices and oil prices, with stock prices leading the oil prices changes. The all share index, resources and financials index were found to be significant variables to explain oil prices. This result is consistent with the business cycle view, which states that oil price fluctuations are mainly driven by demand factors. Furthermore, strong world output growth trends especially in emerging markets, could give rise to an upward surge in oil prices. The study also found that there is a weak correlation between stock price and exchange rate in South Africa. This is consistent with the asset approach. The findings of this study add to the already largely debated theories that seek to explain the relationship between the oil prices, exchange rates and stock market prices. The recommendation of this research is that, policy makers, researchers and investment bankers or fund managers who have interest or trade these financial instruments, may have to consider the role of stock market prices in the various sectors of the economy in their models for forecasting the path of the oil prices and the Rand/US Dollar exchange rate trend