Abstract:
The exchange rate is a crucial economic indicator reflecting a country’s international 
economic health and competitiveness. Following the COVID-19 pandemic and 
subsequent economic instability, the Sri Lankan rupee has experienced significant 
depreciation. This study examines the determinants of the foreign exchange rate in 
Sri Lanka using secondary macroeconomic annual time series data from 1990 to 
2023. Data were obtained from the World Bank and the Central Bank of Sri Lanka, 
with the exchange rate considered the dependent variable. Independent variables 
include the GDP growth rate, foreign direct investment (FDI), inflation, interest rate, 
balance of payments, and trade openness. The Augmented Dickey-Fuller and 
Phillips-Perron tests were used to assess the stationarity of the data, while the 
Autoregressive Distributed Lag (ARDL) model was employed to determine long-run 
relationships among variables. The ARDL bounds test confirmed a co-integration 
relationship, and the error correction model revealed the significant impacts of these 
variables on the exchange rate. The findings indicate that the exchange rate has a 
positive relationship with the balance of payments and inflation and a negative 
relationship with GDP growth and FDI. Interest rates and trade openness exhibit 
mixed effects in the long run, with interest rates showing a positive relationship and 
trade openness a negative one. Overall, the results confirm that all the examined 
variables significantly impact the exchange rate in both the short and long run, 
providing insights for policymakers aiming to stabilize Sri Lanka’s currency and 
macroeconomic environment.