Impact of Interest Rate, Exchange Rate and Inflation on Stock Market Dynamics in Nigeria

This study aimed to assess the impact of inflation, exchange rate, and interest rate on stock market returns and volatility in Nigeria using data from 2000M1 to 2022M9. The Autoregressive Distributed Lag (ARDL) model was employed to investigate the relationship between stock market returns and the independent variables, while the Generalized Auto-Regressive Conditional Heteroskedasticity (GARCH) model was used to examine the impact on stock market volatility. Preliminary tests indicated no serial correlation but heteroskedasticity among the independent variables, which was addressed using the ARDL model with a HAC (Newey-West) covariance matrix adjustment. The results revealed significant stock return effects at a 10% level of significance with a lag of 4, suggesting a link to past performance up to four months. Additionally, the prime lending rate exhibited significance at a lag of 1, indicating the stock market's response to changes in the prime lending rate after one month. However, no significant response was found for changes in the exchange rate and inflation during the study period. The GARCH model showed that all variables, except inflation, significantly impacted stock market volatility. Notably, the maximum lending rate, prime lending rate, interbank rate, and Treasury bill rate had substantial effects on stock market volatility. The study suggests that the monetary authority should focus on interest rate mechanisms for more effective and responsive monetary policy decisions, particularly regarding the stock market.