It is no longer news that Nigeria runs a single-product economy where the only source of revenue for the country is crude oil exportation. Changes in the prices of crude oil in the international market continue to have severe implications on the country's economy's growth rate, exchange rate and even inflation. This study seeks to investigate the impact of four key variables (crude oil price, real exchange rate, inflation and population) on Nigeria’s economic growth. This is to give necessary policy makers a clear direction on the inter-relationship of these explanatory variables on the economic growth of Nigeria. This study employs annual time series data obtained from the World Development Indicator (WDI). Augmented Dickey Fuller (ADF) test was used to determine the presence of unit roots among the variables before the Johansen Before the Johansen Cointegration test and Vector Error Correction Model (VECM) were carried out to determine the co-integration and relationships existing among the variables. The study reveals that all the variables were all integrated at the first order I which necessitated the presence of a long-run of a long-run relationship among the variables; this is further confirmed by the Johansen Cointegration test carried out. The findings of this study clearly show that the explanatory variables used in this study are all significant on the response variable (GDP) in both long-run and short-run. The rise and fall in the prices of crude oil have negatively affected Nigeria’s economic growth, real exchange rate and are equally responsible for the inflationary increase in the country in the long run.

This study seeks to build an appropriate model that will be used to forecast the US Dollar to the Nigerian Naira Exchange Rate. The exchange rate market is known to be unstable; this is due to the constant changes in the economic or market environment of countries. Therefore, forecasting the exchange rate accurately is very important in the economic decisions of countries and the organized private sector. The Autoregressive Integrated Moving Average (ARIMA model) is used as the basis of the time series analysis to forecast the US dollar to Naira Exchange Rate. We also test to check the stationarity condition of the variable using the time plot and Augmented Dickey Fuller. Data used for this study was derived from the Central Bank of Nigeria (CBN) spanning from 2002 to 2022. After model estimation, identification and diagnostic, results show that ARIMA (1, 1, 1) remains a better model to forecast the US dollar to Naira Exchange Rate.